I'm on a Windows 10 i7, 16 GB system with an SSD and I have the current drivers for my video card. The project is mainly 2 4K tracks and is very similar to many other projects I've done with VP14 with no major issues. The same project on VP14 was no speed demon, but was very usable without creating proxies and didn't have any issues with crashes. On VP15, the preview is almost unusable it's so slow even on Draft mode, but worse, VP15 is crashing (not responding) a lot. This is the worst I've seen in many many versions.
I'm not doing anything fancy and the crashes don't seem to be when I do anything in particular. Unfortunately I can't go back to VP14 at this point without losing a lot of work. 😠