As far as I can remember
Matt4u: Smacks em on the lines
Tonedawg: A bit more varied, adds kick serves to annoy short players

Very precise.
Maximo: Also very precise, I usually end up either getting aced, or returning poorly in half his serves, because I have to anticipate and Max seems to read my anticipations very well. I feel we have alot of "mind battle" in our matches, not only on serve, which is really fun.
TOMO's serve is hard and with angle too. If more varied would be destructive
Patko is another good server.
Anyway I think almost everyone here has a good serve. These are just the ones I personally have trouble with because they have alot of angle, so if you don't anticipate right you'll return poorly or get aced.