We went to K1 to celebrate a birthday and had lots of fun. Before you go, do your homework and go with the right expectations and you will have fun too. First, in Austin, this is a new experience. As such, lots of people want to do it. Don;t go expecting to be driving 15 minutes later. The waits can be long, but go with a strategy. We went on a Sunday afternoon at 4:30. We signed in, waited in the cashier line and were told that our first race would not be until 6:30, two hours later. If you know this going in, it's not a problem. We did. So we paid and then left K1 to do other things and returned 30 minutes before our scheduled start time. I would make sure to have some activities planned while you wait, but remember that you can leave during your wait.
The facility was clean; however when racing you may get small rubber pieces (from the car tires) on your clothing, so don't go wearing your best clothes. When you get there, pay attention to the rules or you will get kicked out like the guy in our second race. It's about speed and going fast and you can't do that if you are bumping other cars.
Overall, we had a great time racing and would return again.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.