Guitar Tracks Pro 4 vs SONAR X1 Essential

Well I can be half help here.  I used GTP4 for a year.  Realistically it is a very nice program.  If you are new to computer base recording it is a good intro program, it is powerful, comes with some nice VST and a few VSTI.  I would recommend finding some other VSTI (Native Instruments provides some nice free versions that I used for 6 months before buying their Komplete Elements for more sounds).  There are some limitation with GTP4 and depending on what you are doing you may or may not run into them.  There is a limit to the number of audio tracks you can have in it, also there is a limit to the number of soft synths you can have.  I don't remember the numbers.  

Just before X1 came out, I did the deal that I upgraded to Sonar 8.5 professional with a free download for X1 when it came out.  It was cheap for the program at $250.  I got GTP4 for $100 so overall X1 cost me $350.  Personally I think the upgrade was well worth it.  I got a lot of new tools and plug-ins.  It sounds great and I felt the user interface was better.  I'll likely never go back to GTP4 now even though I had no issue with it when I used it.

The problem I have for you is I'm comparing these for you is I'm using Sonar Professional.  Essentials on the comparison chart doesn't even have half of what came in Professional.   So it becomes trickier in my opinion and which to get somewhat depends on you.

Do you have an audio interface with your computer or plan on buying one separate from your DAW?  If you don't have one and don't want to go buy one, GTP4 has a version for $150 I believe that gives you what you need to get started.  I'm using Line 6 UX2 which I find great for my needs, but that would be an extra $200.  

Are you looking to upgrade to Sonar X1 studio or professional eventually?  If so then you probably want to use Essential because the user interface between X1 and GTP4 is very different.  There wasn't too much of a learning curve going between the programs, but they are different.  There is an upgrade path for both, I haven't looked at the price points for each path though, I suspect upgrading from essential is cheaper than from GTP4.  

The community is also much more active in Sonar than GTP4.  I just jump in here from time to time to answer a couple of questions because I remember what it was like with GTP4 and having not much forum support.  There are a couple of guys that jump in more often than me to help, but most spend their time in the Sonar section.  

It is also worth noting that X1 seems to have pulled the community into 2 sections, people that love it and people that can't use it.  I fall under the crowd that love it.  Since it's release in early Dec, I have had it crash a handful of times, but overall it is very stable for me.  Others haven't been as lucky.  There is suppose to be a massive patch coming out in Feb to fix lots of issues.  Patching for GTP4 is probably done, I could be wrong but in 1 year I saw 1 patch and that was to make it compatible with Win 7. 

My opinion you can't go wrong with either, I'm somewhat bias to tell you go with X1 but I won't lie, if I only had the tools that came in essential I would feel limited.  Obviously money is a factor (it always is for me too), but I would try to get at least studio, if that isn't possible I would go essentials and save to upgrade to professional at some point because the amount of tools and features you get in it is just awesome.  One thing I want to say, don't wait forever to start, if you can't afford X1 studio now and not within the next half year then by all means get GTP4 or X1 Ess.  It is better to start than sit around wishing you had something.   I think they have yearly sales (just before a paid upgrade for Sonar) that you could always take advantage of where the upgrade will be very "cheap"... at least compared to what it normally is

Good luck, I hope this helped at least somewhat.
Matt

Ozzy,
Matt touched on a lot of things. The two audio input limit that Strryder mentioned may or may not be an issue.
While various versions of the software support more inputs, your interface will be the deciding factor.
Which brings us to questions about your system.
What OS are you using?
Computer specs?
What, if any, hardware do you have now?
Consider the need for an interface pretty much a given, if you will be recording anything real time. Onboard audio is not designed for audio recording with sophisticated software.
Have you looked at Music Creator5? It has the same user interface as GTP4, but comes with fewer plug-ins. At $35 for the download, it is a great program to get your feet wet. And the MC forum is one of the best kept secrets around here.
All of this software is quite capable. The real question is which one suits your particular needs.