I can't remember if I've ever had a FreeBSD release panic on a server, but I've seen plenty over the years on laptops. The largest source of panics is drivers, and there's far more diversity (and less testing) in the mobile space than in the server space.
Consider yourself lucky you don't have to deal with radeon drivers! This week alone, I had two different kernel panics, one on my notebook and another on my desktop, both of which use radeon (different gpu models), and in both cases radeon was the culprit.
For the record, I think we all agree that this kind of panic is not FreeBSD's fault. Linux support for this kind of driver is more stable and advanced, but, even though I use FreeBSD both for production and personal use, its "expected" case is production server.
I have kernel panics on 10.3 on a regular basis, varying from several times per day to a couple of times per week according to workload.
There's something inside wait6 and kevent that causes a thread to sleep whilst holding a non-sleepable lock. I hit it more than most I suspect because on my systems a lot of processes are blocked in kqread, whereas with the stock toolset one sees few processes using kevent.
I brought the subject up last year on freebsd-hackers, but nothing came of it.
