Rega RP8 vs Clearaudio Concept

No experience with the Rega.  I had the Concept and really liked the looks and sound of the table, but I have bouncy floors and it is probably the worst table I've owned as far as being sensitive to footfalls, so it had to go.  It sounds like you can put it on something solid, so you should be fine.  I have heard the Ultradeck and I really liked it.  The rest of the components were all different from how I heard to Concept, so I can't say which is "better", but I personally would lean towards the Ultradeck.

I'll keep that in mind if I decide I need to do jumping jacks while listening to vinyl.  I think I'm good for now.  I have a couple of fairly well damped tables both on Symposium bases.  I can walk around the room without them skipping and they do pretty well with the bass frequencies, especially considering they are not ideally placed (in between the speakers) due to space limitations.  There's always something better, but I need to stand pat for a while.