I, personally, use 7 different DAW's, X3, S1, and Cubase, Reaper, among them...

Feature wise - Cubase...hands down, and the added VST's and features of 7.5 are pushing the gap wider...
GUI and Workflow - X3...hands down
Studio One - while it took some getting use to, it is a viable contender...well thought out and implemented.
The problem is, coming from another DAW, it is quite different, and therefore, intimidating.  Once you get 
past that "intimidation" and dig into it, it is a very nice DAW.

One of the most "Feature Packed" DAW's I've used is Samplitude.   Just the Metering options alone contained in 
that package are incredible.  The Audio Engine is pristine..I mean seriously pristine and uncolored.  It also is
one of the most feature rich applications I've used.  It's next on my list to purchase.

The bottom line is always this....

YOU have to decide what is best for YOU.  Get the demo's, if available, and try them before making any decisions...
Find the one that fits YOU best, that makes you the most comfortable, that has the best workflow and features for YOU...and then BUY IT.  Make an "objective" choice by trying before buying.  And there are ample YouTube tutorials to get you familiar with any of them.

That being said, my DAW of choice, because of workflow and GUI, is X3 Pro.

I have worked with just about every DAW out there. When I get new clients it is usually because of the quality work they heard on one of my projects for someone else. When they come by to ask questions," That CD you did for ____________ sounded so good,man! You must have Pro Tools!" I smile and pull up some earlier work and they start flooding me with questions about Sonar. I usually end up with a new client and some pocket change. LOL!
Clients now are a little more open to using another DAW besides Pro Tools. Although, it still is ingrained in them that they must ask for it. Just be prepared to demo some work in Sonar for them and they will usually warm up pretty quick. Also, be sure to explain that any pro studio out there will have the ability to open OMF files. Sonar can save and open those. I have used saving the project as Broadcast wav files. You can toss those into any DAW. Just make sure they understand that they won't have the same plugins. They'll have to either bounce the tracks with the FX or make sure they keep the original audio files to treat in the next DAW. I have a lot of different DAWs on my studio computer but I can safely say I get asked to use Sonar more times than not.

Thanks guys...  I think I am going to skip the PT for now.  Though it is something I intend to learn & become real familiar with along the way. 
  On one hand I get that it seems like it would be best to be really proficient with one DAW.  On the other hand, it seems a bit like saying you should only drive one car FOREVER, this way you get really used to it and know how to run it.  If you never try others how would you A) find that you really appreciate the qualities your car has? or B) realize that maybe it's time for a new car?  Maybe one is better for daily driving while the other is best for getting plywood home from the store?   I am thinking I will continue one with Sonar and at the same time, Dive in with S1 as well.  Learn as I go ya know.  I appreciate it everyone.

Not trying to toot the PT horn but if I was going to invest money in any other DAW it would be PT for the simple fact that you are going to be asked if you have that one program probably three times as much as any other. I would not completely write it off. I just wouldn't make the investment unless there was extra money laying around. Of course, extra money is the hardest kind to come by. It's always a pleasure to come here to learn and share.

Sidroe
Not trying to toot the PT horn but if I was going to invest money in any other DAW it would be PT for the simple fact that you are going to be asked if you have that one program probably three times as much as any other. I would not completely write it off. I just wouldn't make the investment unless there was extra money laying around. Of course, extra money is the hardest kind to come by. It's always a pleasure to come here to learn and share.

Absolutely agree.  I use Cubase for most things and still use Sonar for some but if you have any aspirations of being in the recording business you have to have Protools.  Like or not and you could go on and on  about how other apps are way ahead yada yada yada ... (and you would be correct) but you have to have protools.  It's a fact of the business currently.  Do yourself a favor and just get it now and start learning it.  

ChuckC
Thanks guys...  I think I am going to skip the PT for now.  Though it is something I intend to learn & become real familiar with along the way. 
On one hand I get that it seems like it would be best to be really proficient with one DAW.  On the other hand, it seems a bit like saying you should only drive one car FOREVER, this way you get really used to it and know how to run it.  If you never try others how would you A) find that you really appreciate the qualities your car has? or B) realize that maybe it's time for a new car?  Maybe one is better for daily driving while the other is best for getting plywood home from the store?   I am thinking I will continue one with Sonar and at the same time, Dive in with S1 as well.  Learn as I go ya know.  I appreciate it everyone.

That's a good plan...

Just remember, you don't know anything about a car without at least "test driving" it....

Same with a DAW.

For the most part, they all function pretty much the same, it's just the differences in the "How to get there"!
Just like a car, they all do basically the same thing...get you from point A to point B.  

I was just in a studio last week that runs PT and they were asking me a lot about Sonar.  Not sure why...they're all Mac too.  Anyway, I'm not that familiar with PT as I don't use it, but looking at their monitors, it looked amazingly like Sonar that I felt I could jump in and start using it.  Give me 40 quality hours on it, I think I'd feel comfortable.
 
That said, I agree if you're running a *serious*  studio, without a doubt, I'd use PT.  UNLESS you're already getting clients that come to you, because of YOU and the final product.  If you're getting a lot of tire kickers, you'll not convince them.  Lots of *young* bands know *too much* and think PT is the only serious platform.  

ChuckC
Thanks guys...  I think I am going to skip the PT for now.  Though it is something I intend to learn & become real familiar with along the way. 
On one hand I get that it seems like it would be best to be really proficient with one DAW.  On the other hand, it seems a bit like saying you should only drive one car FOREVER, this way you get really used to it and know how to run it.  If you never try others how would you A) find that you really appreciate the qualities your car has? or B) realize that maybe it's time for a new car?  Maybe one is better for daily driving while the other is best for getting plywood home from the store?   I am thinking I will continue one with Sonar and at the same time, Dive in with S1 as well.  Learn as I go ya know.  I appreciate it everyone.

Good call! Studio One would be my pick too. The mastering section is what sets it apart for me. You should upgrade to X3 as well...it rocks!

Hey Chuck, you should send a PM to Danny Danzi. He's got it all going on and working in multiple studio's with multiple DAW set ups. I would respect his views on this.
 
I have Sonar, Reaper and Studio 1. Now that X3 is out I won't be using anything but Sonar since I don't have any dedicated hardware to use. X3 is much better than any Sonar to date. I think the results you get are more important than the tools you use.

One of the things DAWS have done is blur the lines between producer and audio engineer, particularly in pop music. If you are primarily some form of audio engineer and working out of a full fledged studio, Pro tools (with all the accompanying hardware) is the way to go.  Most recordings distributed on a large scale end up there, even if they don't start there.  If you are more artist/musician or producer, that mandate is not nearly as clear. Plenty of top producers do most of the heavy lifting in other software (order of popularity varies by genre) and then get sent for final mixing in Pro Tools, usually by someone else.
 
IMHO a move from Sonar to Studio One is a lateral one unless Sonar is somehow failing you in some area.  It just means you have to relearn what you already know and abandon experience. I tried S1, it was ok and I am sure if I somehow got stuck using it as my sole DAW, i would adapt, but nothing screams at me "clearly superior".  Same goes for Cubase. Definitely features I liked better but some things I liked less.