I've only been on B&M coasters so far (because there are three next to my house) so currently my opinion is biased towards B&M right now, but I'm dying to ride any kind of Intamin coaster.
Judging by the few coasters I've ridden...
Alpengeist - My current #1 coaster. The ride is fun & intense as well as highly underrated.
AC - My number 2 coaster. I think a theme needs to be added. Has some very good airtime in the back.
Griffon - My number 4 coaster. Fun coaster but feels gimmicky, I think Busch only built this coaster because Tampa got one. No theme or shade whatsoever
Hopefully I'll be able to visit KD or some other park this year and expand my coaster count.