I had heard great things about Kristen, who unfortunately only teaches 1x a week at Equinox NYC (I believe she teaches out on Long Island as well). First off, she's got a killer body and clearly knows her stuff. Her personality is fantastic - she seems to really care about her students and is focused on encouraging riders and pushing them to their max. She was on the bike the entire time, taking short breaks to yell words of encouragement. There were a lot of heavy hills and some standing climbs as well as bursts/breakaways. It was definitely a challenging class - very similar to an outdoor ride. She had us envision ourselves on a race course trying to overcome our competitors which was a lot of fun and awesome motivation. I would definitely go back to her class.