I say Go! See for yourself how close the kids that participate are, and how much fun they have. Our girls ran the OCCA shows in Oklahoma for a few years, and really enjoyed the banquets even when they weren't receiving an award. The OCCA, and the Junior National shows were their main motivators to excell with their cattle. But the biggest benefit was the real, personal relationships that developed among those kids who really got involved.
I'm sure the TJLA is like anything else. You get out of it, only as much as you put into it. Jump In!!!