Enigma is the only choice for clothes-independant AIWB. Check out Tessa Booth for examples and Deep Carry theory.
The Mete should be good, just make sure whichever one you pick fits. The Prime is roughly the size of a Glock 43x MOS which is the sweet spot for many people. I find the G43 conceals better (MC9 size).
Fits as in, there is room for your support hand on the grip between your strong hand fingers and strong hand heel, and the trigger reach isn't too much or too little. If you are gripping your fingers or cranking down on your strong hand you won't be able to hit anything or recover consistantly between shots. Joel Park explains this well. Many gun counter workers think that fit is how good a gun feels in your hand, this does not affect how it will shoot.
Tenicor and Joel Park are excellent resources for shooting technique, they promote a progressive style that is easy to learn and apply and gets results.
If you don't already plan to get one, an optic will increase your functional ability by a lot compared to iron sights.
Hornady Critical Defense 124gr +P and Federal HST ammo was found to be the best by probably the most comprehensive and scientific study of handgun ballistics ever, the one the FBI did in the 90s/2000s.