A few months ago I switched to EMC to try it out. After running there for a week or so I notice my payout dropped by 10-15% vs. other pools. The luck seemed to be about average but there were constant connection and other issues. Inaba kept posting that it was this or that issue and no worries it's fixed, but then a day later it would crap out again. This was around when he introduced the diff server which seemed to knock out the us1,2,3 servers.
It was clear Inaba has no idea how to run a production server as he was treating production like a test environment. Mistakes all over the place, and very defensive reactions. One time I posted a strange block time artifact, he replied that it was fixed and how could I be so stupid as to post that. But his original reply that it was fixed happened BEFORE the time stamp on the problem I brought up, so obviously it wasn't fixed. Childish.
The thing is you can't do this with ASICs, you have to be 100% fully tested and 100% confident before tape-out. I used to be in the field and have completed many designs, mistakes can not be allowed. If EMC is any indication of BFL's quality control, I'd be worried if I was a pre-order customer there...