I shoot IDPA with Texas Tactical. It's a good group. Match director Mike Webb does a good job. There are matches this weekend on Saturday at Cedar Ridge (just east of Bulverde on FM 1863) and Sunday at Austin Rifle Club in Manor. This weekends' matches are combined carbine/ pistol match - you can shoot pistol or rifle (AR/AK types) or both. Plenty of folks will be shooting handgun only.
Your setup is fine. Just be VERY conscious about muzzling yourself while re-holstering (automatic DQ if you do). I often use my similar Comp Tac holster. But I've seen some folks who use their off hand to clear clothing around holster and then muzzle that hand.
Be sure you have at least 3 mags, two mag pouches (or one plus a pocket), and about 100-150 rounds of ammo.
Give it a try, you'll enjoy it.
And unlike c-dub I recommend you "bring your toys" and "play the game" the first time. I also showed up my first time "just to watch" but was kicking myself after first stage because it looked like (and is) so much fun.