In my relatively limited experience... Tabasco is both my favorite drying variety as well as my favorite "snack" (eat straight off the plant) variety. Excellent taste as a powder, and not so ridiculously hot that it can't be eaten whole fresh off the plant.
My favorite jalapenos are the Jalapeno M and Biker Billy Hybrid.
I really like the Rocoto Red, for both its unique flavor and the freaking INSANE growth the plant puts on. It really let me down last year, then just as I was about to toss it to the curb in fall and call it a failure, I noticed a little hidden pepper starting to ripen on it. Now the thing's going so nuts, I don't know how I'll bring it indoors for its tons of fruits to ripen...
The Hot Lemon was a really good variety, although it grew so big and required more water (ie. it needed a much bigger pot) that the plant was sort of a chore to take care of. It's awesome sliced up and put in spaghetti, though.
Many of my favorites are C. chinenses though, but this is also the species I've tried the most varieties of. The problem is, I've had a hell of a lot of good ones, but also several not-so-good one. There are too many good ones to list, and I'm trying to refine my list of favorites... but it's hard to do.