Let me start by saying that I love PRE, but I agree that it can be very flaky.
If I had a nickel for every time it just crashed when I tried to do ____ (fill in the blank), I could afford the Premiere Pro version.
However, I think that at least some of the times it's a case of shooting the messenger. PRE depends on many other actors: video drivers, audio drivers, Windows memory management, etc. etc. and it could very well be that PRE is doing everything correctly and it's these other software components that are behaving badly.
For example, in PRE3 I had a situation where opening a particular DV-AVI file would cause PRE to crash. After several days of Googling, I finally discovered it was a bug in Windows itself having to do with thumbnail generation for DV-AVI files. Premiere was simply asking Windows to display a list of files, Windows' response was to crash, which in turn caused Premiere to crash.
Could PRE have handled the situation more gracefully? Well, probably. But we seriously can't expect Adobe to plan for every possible Windows bug. And nVidia bug. And Turtle Beach bug.
I think many times the flakiness we see in PRE - and blame on PRE - is really flakiness of the underlying subsystems.
Why PRE has issues and Sony (or others don't)... dunno. I'm sure that PRE has bugs - I've found more than one that had nothing to do with Windows, et. al. It might also be that PRE has more power and stresses these components more. I think it's interesting to note if you look through these forums how many "Premiere" bugs have been solved by upgrading video drivers, audio drivers, Quicktime and optimizing the box it runs on (defrag, free space, memory, etc.).
On one hand, I think Adobe's built an incredible piece of software, especially for the price. On the other hand, especially lately I think they have focused on adding dubious features and dropping the ball on Q.A. Especially frustrating is bugs that pop up are RARELY, if ever, fixed via an update. You have to wait - and pay for - the next version and hope the bug is fixed. And sometimes not even then.
Their Lightroom product had version 1.0, 1.1, 1.2. 1.3. 1.4 that dealt with bug issues and support for emerging technology. Where is PRE v4.1, 4.2, 4.3???
Just my thoughts.