Honestly, I haven’t had many problems, aside from the 50-character limit on day one. I like the dark theme, navigation has been fine, no login problems, no staying logged in problems, and I LOVE the fact that just opening a thread takes me immediately to where I last left off.
It’s different, but not in a totally bad way. I know it’s a huge change after over 20 years (I started lurking the SDMB sometime in late '99 or '00), but I think overall it’s great.