That's my experience too. For some reason the desktop after startup looks amazing... but as soon as I start playing around with the applications I get a lot of

That's my experience too. For some reason the desktop after startup looks amazing... but as soon as I start playing around with the applications I get a lot of crashes, things in the desktop that don't make sense and general slowness. I think I've made this comment before, but it almost feels like new KDE releases are optimized for screenshots: it looks great, until you click on something.