This list is in no particular order, just off the top of my head.
There are too many shady characters in MMA, IMO. The good thing is that word spreads fast when service is bad, the bad thing is that not everyone listens.
The following are those from whom I've received consistent excellent service:
JenBJJ.com
GroundFighter.com
Sprawl.tv
Amazon.com/Amazon.ca
Islandmartialarts.com
There are others including howardliu.com, atamakimonos.com, etc. from whom I've received excellent service but from whom I've only ordered once. I've placed second orders recently with onthemat.com and bjjtapes.com, so hopefully those will be repeatable as well soon!
At RAZE we pride ourselves on consistently having some of the fastest turnaround times to get you your gear ASAP!!! Nobody likes to wait for their stuff when they order over the net so we process and ship all orders either on the same or at the latest, the very next business day from when they are received.
We know that customer service is vitally important to building repeat clientelle and we know that word travels (especially if the customer service is poor) so we do everything we can to accomodate our customers and to show our appreciation for their business.