I had never done a full Zumba class before (just as a pre-5k warm up) and wasn't sure what to expect.  Frank made me feel very comfortable, advising that if something wasn't comfortable to just keep moving and jump back in when I could.  I love the fact that he mixes his playlists up, so its not all just  latin or hip hop, and the songs are difference class to class.  I also really like Frank's style of instruction.  He does the moves along with you and uses hand motions or quick whistles to let you know the moves will be changing momentarily. I've gone twice so far, and just signed up for a third session!