There appear to be many negative reviews of this place but I can honestly say we had a blast. We raced with a super-groupon deal so that our family of 4 had 2 races each.
The kids started with the junior carts and that was the right call as neither really had much experience driving carts (Mario Kart doesn't count) so they were a bit cautious at first. However, in their second race they put the pedal to the metal and tested the limits of their speed-limited carts.
The adults took the big carts for a run and I was lucky to be racing with novices and took the checkered flag in one of the two races. I was foiled by a "pile up" in one of the races which killed my lap average. :) My lovely wife took a nice stroll around the course and it was fun to wave as I zipped by.
The service was excellent. The track-workers were hilarious. All in all a great experience.
** note ** Our first attempt to race was marred by the company Groupon and their multi-hour outage in March 2015. We did not print the groupon, we couldn't pull it up on our phones, and they had no way to help us over the phone (30+ min wait to tell us that). Clearly this had nothing to do with K1, and they were trying to help us, and other than just giving us the races for free I'm not sure they could have done more.