A. DX has better servers and a better set up than RealGM
Actually, RealGM has 6 servers. DX has two. And DX actually only has two because I "borrowed" one from work to use as a squid image cache for draft night.
The real difference is that DX has a professional linux sysadmin and dba, and realgm doesn't. I've optimized the *shit* out of DraftExpress. 90% of queries are hitting the query cache, and 99% of the queries that don't hit the image cache are hitting indexes. You can literally count the # of sequential scans being performed on the DX database on your hands. We also (probably, I don't know RealGM's disk configuration) disk configuration that's allowing 1500 queries/second to only have a 0.3 iowait.
(sorry for boring down the board with technical mumbo jumbo).