I got RC1 built tonight. Oddly, I was installing the soundcard & it BSOD'ed (always the soundcard!) & went a bit unstable after that, so I've wiped the drive & will start again tomorrow.
What I saw of it, was very smooth, quick & polished, as compared against beta builds of the same sweet os. it will be good, I have no doubt. You'll be pleased to know GG that the desktop revolves nicely, without end.