I've used
Cubase (but not for a long time),
Logic (from 4 onwards, still use it sometimes),
ProTools (but only in larger studios, never for my own projects),
Ableton (still use it a lot),
Reason (but before it could be considered a DAW)

Almost every DAW has a few features that all the others are missing. Features from other DAWs that I don't own but would like to see in Sonar are:
- Easier beat extraction/time warping from Ableton
- Non destructive quantize from Logic
- The powerful/fast step sequencer based editing from FruityLoops
- Note expression from Cubase

Obviously there are many more but those would make a huge difference for my workflow. That said, most of my productions use a lot of software instruments and live vocals so the Melodyne integration via ARA has been a spectacular upgrade for me, and none of those DAWs have it (though they have their own proprietary pitch/time solutions).

Music X. An early 90s Amiga application, MIDI sequencing only if I recall correctly.
Cubasis. Again, early/mid 90s. Buggy, incomplete in many ways and the current iOS version of Cubasis blows it away. As it should, an ipad is a bit more powerful than a 486 PC, even if the PC did have a massive 4 megabytes of RAM. And it was a cheaper way into
Cubase. Used it until I discovered Sonar (version 4 I think) and found I much prefer Sonar.
Pro Tools. I've sat in a studio or two and tried to sort out a few things like eq settings or mix levels I couldn't find an adequate way to explain to the engineer. Never owned it. It used to be expensive and tied to limited and very expensive hardware. MIDI was non-existent or nearly so, unique third party plugin format.... Basically a step backwards from Sonar in many ways.
Live. I just don't like it, nor the instruments, nor the effects or the workflow and I've little use for bundled loops. Though I have used Live Lite at the rare times I've needed to take some synths and something to flexibly send MIDI to hardware somewhere.

Currently using Logic Pro and awaiting MacOS Sonar. Current only PC is unreliable and Windows 10 is a very good reason not to spend money to replace/rebuild it when we've Macs anyway.

I also have the basic version of Mixbus, which is interesting and it certainly does have a recognisably "American studio" kind of quality to its audio. Whether that's better or worse than any of the other console amd channel strip emulators around or even no console emulation at all is a matter of taste really. It's the only DAW I consider two screens pretty much essential for, though more than one screen helps a lot with any DAW.

I have a lot of DAWs. I don't dare list them all and I probably couldn't do it accurately.  I prefer FL and Live over Sonar only because it works better for what I do.   Orchestra stuff I leave for Sonar. I'm a polygamist when it comes to DAWs. 

- Sonar Plat : My current main DAW. Also use Pro Audio 9 before.
- Live : My previous main daw.
- Reason : Still using it, I like the concept to use only the tools you have and spent more time on making music. And since version 6 it can record audio so I don't need to rewire to other DAWs which is real pain to me lol. But sometime when working with so many instrument/effect tracks, the Reason's rack gui is a bit mess.
- Cubase : Have a change to try since SX to Pro 9 now but never has a change to use it seriously.
- FL Studio : Like cubase, familiar since it call FruityLoops but never use it seriously. I don't like the gui.
- Acid : Love the concept of acidized. Use it before Ableton Live has been introduced.

cakewalk pro audio, sonar, tracktion, reason, live, studio one, auria pro, project5, cubase, mixbus
but these days i actually only use, in order of most used:
studio one
live
auria
sonar
mixbus
 
/fwiw

my first was Sony Acid... v2 ~1999.  Actually i think i had v1 but got rid of the floppy, lol.
I still own Acid because of the ease of use when messing with samples, and my first 2 albums were done on that software.  I demo'd FL long ago.  Live is more for DJ/live use, and i couldn't find a bargain on it.
Took a big step and went to Cubase 4? for a while but it was just too clunky... had to spend time looking everything up.  Tried Sonar demo but not crazy about it back then... a lot like Cubase.  
Got Reason and used it for some songs on an album but it just seems more like a primarily synth-based daw.  Learning curve is different from mainstream DAWs, so my brain got overloaded... i needed to simplify.  Started working with Reaper, which I still have and like but don't do much pro stuff with it.  I did some album tracks on it also which worked out well.  I'll open it up to record some midi or sample stuff for transfer to my keyboards.  
Been using SPLAT for a few years now and like it mostly because of the included features and fx, prochannel, etc.  I usually changed DAWS when a price deal/crossgrade became available for them.

MandolinPicker
Started with a very simple DAW called Kristal Audio (http://www.kreatives.org/kristal/) which eventually became Studio One (although I've never used Studio One). Have used Audacity but didn't really care for it. We use Reaper 5 at our church and it does the job. Started with Cakewalk using Home Studio 2002 and been updating/upgrading on and off with them ever since through Platinum Lifetime.
 
What I have found is that each DAW does pretty much the same thing, but they each do it in a different way. You need to find the DAW that works well for what you want to do and how you want to do it. For me, that is Sonar. YMMV.

I started with the same, though at the time was kind of like cubase did not know i morphed into Studio One. Actually was using standalone Digital Recorders before Kristal and before that a couple of 4 track reel to reels.
My PC was so crap at the time it would run Protools on the Delta Soundcard. Was still on standalones for ages but eventually upgraded PC and was going to get Cubase SX3 when a friend turned me onto Sonar 6 he was using on his PC.  I used a free LE version of Samplitude that came as a CD on a Music mag just after I got S6.
Have skipped a few upgrades up to X2. Somewhere in there when Reaper was a buzz that was as good as the big guys I bought at $50 lifetime support. Only thing is I could not get Reaper to work so stayed on Sonar. Samplitude though easy enough didnt have the appeal of Sonar maybe because Sonar 6 Pro Cost more and was a bigger investment to get the most out of.
 
I feel it is best to put all your eggs in one basket when it comes to learning a DAW.
 

for me i first used cakewalk pro audio 8/9, then have had all versions from then on, always the top version, now i have platinum (lifetime). had and used reaper ever since reaper was. tried out studio one 3 professional on release and that was that, no turning back, does everything i need in a way which just clicks with me, absolutely rock solid, love the features, i use it 99% of the time. have started using platinum a bit more recently, but studio one 3 is still where it's at for me. i could mention mixbus, but i wont

I've looked at Cubase, for all of about 30 minutes. There was nothing compelling to me compared to Sonar. Other software I've owned; CoolEdit  Pro (MultiTrack) (way back in the day); Sony Vegas; Sony Acid, Sony Sound Forge.

Studio One 
 
Reason 
 
Ableton Live 
 
Logic
 
Cubase 
 
Reaper 
 
Sonar x1 ,x2 , x3 ,Platinum