[KenpoTex]

Any of those should be ok...I personally prefer an open-topped IWB (inside waistband) for day-to-day concealment, but to each his own. The thumb-break won't give you any problems if you train to use it. If you buy one with a thumb-break or other retention device, just make sure you engage it EVERY TIME you holster the weapon. Don't cheat yourself by leaving it disengaged when you practice (dry-fire, range, whatever) or you will create a problem.

One thing I would advise is to buy a holster with belt-loops that exactly fit your belt. In other words, don't buy a holster with 1 3/4" loops if your belt is only 1 1/4" or 1 1/2" wide (basically, avoid the "one size fits all" loops). Loops that fit your belt will make the holster more stable since the holster can't "rock" back and forth.