I recently bought a 06' 8ft Pro Centurion & had it set up. The K55 rails are in great shape and slate was perfect. (One owner original). Still had original Brunswick Cloth. (Swapped top Andy's 988)
I'm very pleased with my table & I love the looks of it. I have never owned a GC, but have played on SEVERAL.
The thing about the Centurion is that it's a Commercial Grade table, but it's very straight forward and easy to maintain. (I did need to trim down the corners of my drop pockets).
GC's are built like a brick-shit-house, and from what I've heard can be a pain to work on, compared to other tables.
I couldn't find a GC around me for less then $2500 at the time I was looking, so I feel like I have a great playing table and great value.
Now if.. say I found a GC that was in as good of shape as my Centurion for the same $$, then I'd buy it.