Time to upgrade?

So I've been sitting on Cakewalk Music Creator 3 (3, for cripes sake!) for over a year and a half now. I realize that it's time to upgrade, and I finally have the means to do it. Of course I want to go Cakewalk again. But the thing is, which product will meet my needs? How will  be able to find out (I used up my trial XP) ?
 
My main goal is to get unlimited (or HIGH AMOUNTS) of audio FX and VST instruments into singular projects. Additionally, I need one which is stable on Win7.
Could you guys just throw tons of suggestions at me? And reasons why?

If it's high amounts of FX and VSTi's that you're after, then the most important upgrade you need to concentrate on is your machine, and that means a faster processor (if your current one is not up to it) and enough memory (at least 8GB). If you're using lots of VSTi's then 64-bit Windows and 64-bit Sonar is a must, since your DAW only sees a limited amount of memory in 32-bit. 
 
If your current machine meets these specifications, then I would say go with whichever version of Sonar agrees with your budget. It's going to be a step up from MC3 for sure. However, I wouldn't restrict myself to just looking at Sonar - if you're into electronic music then some of the features in programs like Ableton or Reason may interest you as well. Or if you want an incredibly powerful DAW for an insanely cheap price, then look at Reaper (there is a demo). 
 
If you're set on Sonar then the Cakewalk website has a detailed comparison table which lays out the differences between versions.
 
http://www.cakewalk.com/products/SONAR/SONAR-X2-comp-chart.pdf
 
Of course Producer offers the most features, but most of that comes in the form of extra plugins and instruments. Some people would say that you can make damn fine music entirely with free plugs, which means spending the extra on Producer isn't the be all and end all. However if your budget stretches to it then go for it....the mixing effects (ProChannel etc) are excellent. 

You should be alright with those specs. Mine are only a little higher and I seem to do alright with the plethora of VSTi's and plugs which build up in my projects. Sometimes I have to jack up the buffers or freeze stuff if things get too dense, but it's no big deal. It's not as if I'm streaming entire orchestras worth of samples or anything. Honestly, I would sit down and think about what it is about MC3 that isn't doing it for you, and look at the specs of each version of Sonar to figure out which version will fill those gaps. 

Also, you might want to try posting this in the Sonar forum because you'll get a lot more suggestions and input there. 

Running MC4, X1 Studio and X2 Essential here, with X2 Studio and Producer in the shrinkwrap awaiting installation. All 3 are stable and productive.
 
I recommend upgrading to X2, so you don't have multiple learning curves that can interfere with each other, and so you have the longest period of time to work with ONE platform, so as to get the most productivity and efficiency out of it, before it and your computer force an upgrade, transfer of projects, and a new learning curve.
 
Before you start, steel yourself to avoid getting bogged down in bells, whistles, plugins, synths, etc. Right from the start, focus on the music and treat all the buttons and knobs as tools, not the end result. Remind yourself of that at least once a week.
 
The Cakewalk videos are a good way to get up to speed quickly on operating the major components.

So I bit the bullet and purchased X2 Studio. it was $150 off on Sweetwater, so I couldn't have found a better deal- plus, dat customer service. Hopefully this is the next big step in my music production!!!!!