Gymkata did blow. The star was a former Olympic gymnast (Kurt Thomas?) who was once a household name. I also think it was (another) typically bad post-Enter the Dragon Robert Clouse-directed movie.

Simon Yuen (Yuen Siu-Tin) was very cool. (He also plays Fu Sheng's Crane-style teacher in my fave MA movie, Shaolin Martial Arts).

I remember Ernie Reyes Jr. way back when he was an 8 year old with his dad's West Coast Demo Team. As far as Tae Kwon Do technique-wise, he's very good. But he can't seem to act, and the choices he (or his father) made for him in the movie/TV industry aren't good. Also, that old karate tournament demo style (overdone kiyai-ing, overdone faces and gestures, etc.) just does not translate well at all in the movies.
And when he does get parts, at least as an adult now, he always has to talk as if his English is bad, or like a fortune cookie. Too bad.