Sonar 8.02 x86 @ Windows 7 x64, will stability/performance get better if I upgrade?

Well, it's been a while, again. :) I was a regular on this forum from 2004-2007 and made a slight return in 2009 when I was mixing an album by the Swedish band Bibleblack. That was the last one in a row of metal albums passing through my DAW, and by that time I realized I hated it. So I quit. :) Sold off most of my hardware and uninstalled most of the software. But here I am again, JUST FOR FUN this time! I've re-installed Sonar (almost 10 months ago) and some old plugins that I know from the "before-time", and I've started to learn everything from the bottom, basically. Thing is, I'm still on Sonar 8.0.2. As far as I can tell it's a stable system. I'm running the 32-bit version under 64-bit Windows 7 (due to the fact that the 64-bit Sonar did NOT like most of my old plugins, and I need them to live). But I need some hard facts here: - Will a upgrade to 8.5, X1, X2 or whatever result in a performance gain and/or increased stability? I rarely use the included plugins or instruments, I prefer to use the ones I know from before, so that's not a selling point that works on me. :) I have a quad core system, and I can tell that Sonar utilizes all four cores in a great way. The load is even between the cores. I haven't had a single Sonar crash since I started running it in the current configuration (x86 on x64), besides a "crash on exit" that happened ONCE. So to summarize: should I upgrade or stay at 8.0.2? Thanks!!

So maybe I'll just stick with the x86 8.0.2 version for now. After all, it works.

If your software has all the features you need and is stable then I would not upgrade. 
As said, you can install multiple versions of Sonar and try them out and see how it goes. 
I tried the trial version of X1 for a month and saw no need to upgrade so I carry on with what I have  without issues. 

If your like me and record mostly real audio then you don't need a lot of memory. It's VST's that need you to go to a  64 bit system.  

You can only use just shy of 3 Gigs of RAM under 32 bit. 
But if it's not jamming up then your fine. I found I could not use Session Drummer with the 32 Bit system and 2 Gigs of RAM. 

Bitflipper is right, no need to upgrade especially if you aren't sold on the new features of X1/X2. More and more VST makers are making 64bit versions of their plugins so I do think that eventually you will want to go 64bit.