I've experienced no problems with raytracing.  Although I have had a couple of render "lock-ups" -- which consisted of clicking on the 'render' button -- and then having nothing happen.  It wasn't actually a 'lock-up' per se: it was more like a refusal to begin rendering.

However, once again: I found that if I exited P7, and then started it back up again -- after the freash start-up, the scene rendered out just fine.

Is P7 perfect?  Nope.  Is it an improvement over former versions?  Definitely.  Yes.  And then some.

Something To Do At 3:00AM