Without a doubt the best place in Las Vegas. Without a Groupon it's comparable to any other less worthy location. With a Groupon it's an absolute steal. $27 for 2 good length races. Worth every penny and then some.
About the track: It's more challenging than it may look. Lots of areas where it's real smooth so kart control gets entertainingly difficult. The track is wide enough to make passing easier than I've experienced on other tracks. It's long enough and has enough turns so that if you have a small group you can all have plenty of your own space.
Karts: Awesome karts. Seriously. They don't lose power crazy bad in turns like other tracks I've been to. They all weren't drastically different like other places I've been to. They all seemed to have very similar speed and control. A lot of other places I've been to have karts that are noticeably better than others. Not an issue here.
Staff: Really friendly staff. Really helpful. They pay attention to the race while you're racing!!! A huge game changer for me. If someone has an issue they are quick to help. It is easy to tell that safety is important to the staff.