Thinking of doing an Exterra Sprint Tri in Vegas

I've done several western XTERRAs, and my advice for you is to hold off and learn to mountain bike first. A race isn't the place to learn. I'd rank the XTERRA courses as solid intermediate level mountain biking, not beginner. The sprint version of the Vegas course is 1 loop, while the regional championship course is 2 loops. They are usually challenging for the championships as slots to the world championships are up for grabs.

The mountain bike portion is, unfortunately, the one where the most injuries usually occur (broken bones, etc). For newbies, it's not the fitness that's the limiter, but the technical skill. That lack of skill can lead to injuries, including to other racers. So don't rush into it, and instead get a bike and start riding the local trails and see if you even like mountain biking first. Then work on the basic skills, enter a few local mountain bike races, and then do an XTERRA. But to do this race on a whim with no mountain bike experience would be taking more than a few risks. It would be a long flight back home if something happens.

The XTERRA series will be around next year.