I might be building a new desktop. This is an "Addition" to my existing system, which uses Sonar 7PE 32 Bit. O.K. great for me, right? But here is the hitch. I have a system working now that I record (only) with and it is Win7 32 Bit, using Sonar 7PE. Sounds good right? It is, but if I build a new desktop, should I just pull the trigger and use Sonar X2, 32 Bit or 64 Bit. Will X2 work with the audio files created on Sonar 7PE? Will Sonar 7PE audio files created on a 32 Bit system work with X2, 32 or 64 Bit? If you say "Yes" upgrade, then please state what bit and "WHY", not bit, but why upgrade? Just because I have a new desktop does not mean I need to get another release of Sonar. And if I get a new release will I hate and not use the Sonar 7PE release? I think you get it. I need to here from experts on this or at least someone who has done something VERY close if not exactly what I plan to do. Thanks Everyone.

An audio file is an audio file no matter what system it is recorded on. So ones imported it will play. Its where you save as different types of projects that causes the issues such as .cwp project might give some issues if imported into sonar x2 and it has plugins attached that are no longer available in x2.
Sonar x2 is  and works well (the same as most other daws) but if you have freebie 3rd party vst's they may cause all types of problems and  users then blame the X2.  

Definitely go to 64-bit Windows.