I recently got GVI to replace GS3. I'm very happy with it so far. One thing is I've noticed I can load many more instruments than I could in GS3. I still don't know what the limit is. Must be using some DFD extensions or something. And now I found out I can create keyswitches to cut in and out instruments on a stacked channel. Best of all, I haven't had a single crash.
P.S. got ExSC for sample conversion. That works great too!