I really like the concept of improv edited down into sketches. You get the spontaneity that makes improv great, minus all the countless ways in which improv is positively unbearable. The hyperfast pace of the editing is great, too, and gives it a really nice old-school radio comedy vibe.
I've only had a chance to listen to a little bit of one of the episodes, but I loved the FM radio DJ tryouts sketch. I will listen to more when time allows.