I'm running Studio 20 v5 with the CC-590 v5 centre and I really like the studio centre. Doesn't seem to have the same brightness that the 20's have.
@stalag2005 in the
Paradigm Owners thread has the 800F but is using the Prestige 45C centre. He might be able to comment on the Premier centre? The centre you have now might pair well with the Premiers if you don't mind non-matching exteriors.
The v5 Studios are good speakers already, so I was looking at the Founder 80F (the 100F is still out of my price league). Paired with the 70LCR that would make a great setup, although 3 of the 70LCR with a sub would work great as well. My local dealer has the 80F on display so I'm just trying to find the time to demo a pair.