Well, don't have/haven't had that many, so not too much to choose from:
a) Best - my HerbalAire 2.1 I'm in LOVE with it! (can't get to grips with Direct Draw, I use bags only)
b) In-betweeners:
MFLB - use it on the go, but don't touch it indoors. Don't LOVE it, but don't dislike it either...