Hi..
I also work at Randolph AFB. We just had a new dealer take on Triumph here in San Antonio this year. Alamo BMW/Triumph
http://www.alamopowersports.com/default.asp The dealership is about 25 miles away from Randolph. The next closest is Lone Star BMW/Triumph in Austin which is about 90 miles away.
I haven't had any service done by them yet either, but have ordered a few parts through them with no problems. I will probably have them put a rear tire on my Rocket this week or next.
It's a really nice, brand new facility. Not only are they a bike dealership, but they are also heavy into older sports car and kart racing, and actually have kart track on site.
There's some really nice riding for that Sprint around here too.