my biggest gripe with Vegas has always been the terribly slow and stuttering prehistoric preview. More powerful GPU and 32gig of RAM have brought no significant improvement, and it's been my (almost sole) biggest frustration in my workflow with Vegas, although I'd defend it over any NLE out there anytime.
Edius 8, I tried it, and wow - it's lightyears ahead in that department, you can throw titles, grading, FX onto it and their preview is fast as lightning and you can STACK GPU cards!
So before I spend $$ on the V14 upgrade and run into the same issue - has V14 got improved preview playback? Anything else that speaks against the upgrade?