Sonar X1 on XP 32 bit

 I am looking for advice if it's worth upgrading to Windows 7, 64 bit. Sonar X1a is actually running pretty well without many crashes. I too am patiently waiting on the X1b release. My basic recording is mostly audio 20-50 tracks, with several plug in's running. I haven't been worried about the 2 gig of ram because I don't use a lot of loops and usually bounce them down to an audio track and then remove them from the project. I realize that Windows 7 would need more Ram. I also don't use the soft synths much either. I just record midi tracks and record outboard gear to audio. Reverbs (Lexicon) are usually in 2-3 busses for the subgroups. Other than Waves RCL, all other plugs were included in the various versions of Sonar. The only other software on the computer other than Sonar 7, 8.5 and X1 is Sound Forge 9.
 
The computer is a Dell Precision 390 with a Quad core Q6600 @ 2.40 Ghz, and 2 gig of ram. This machine appears to be a 64 bit machine. In the BIOS, it says under processor, 64bit, "yes". Windows is XP pro x86, 32 bit.
Interface is a MOTU 2408 mkII with a PCI-324 from the Cakewalk Pro Audio 8 days. The performance meters are hovering around 25%, Disk is about 10% and memory is about 20% during playback with everything enabled.
 
So, for the time and expense of upgrading to Windows 7 64 bit, adding more Ram and upgrading the PCI-324 to a PCI-424, would I really see that much gain in performance and stability?
 
Thanks,
 
LTG