I don't find AIWB comfortable at all. Maybe it is just my body shape, or maybe I'm doing it wrong, but nonetheless, I'm not doing it.
I carry a G19 with a TLR7a or a G26 with a TLR6 at 3 o'clock IWB with an FBI cant. With this position I can easily bend forward at the waist without the gun digging into me. I can also squat or bend forwards without the butt of the gun sticking out like a flag like it would at 4 o'clock. It is also comfortable to sit, whether in a car or any other seat. The only drawback is access while seated and belted in a car.
I am a great advocate of carrying with a loaded chamber. Your draw stroke is much simpler without the extra steps of charging the gun before you present it.
Additionally, you may not have the time to rack in a round.
If you're sure you want to carry this way, practice, practice and practice some more getting the gun out of the holster and charged so you can do it instinctively if you ever need to. Include practicing doing it without your support hand. - NB. use dummy ammo or snap caps, not live ammo while practicing this.
When I say practice, I mean hundreds, if not thousands of reps. Don't just to it a couple of times and call it good. Through practice and competition I have drawn my gun countless times, and I still practice it regularly. Gun handling is a perishable skill. I also pay attention to changes in equipment. Drawing from an IWB holster is not the same as my OWB holsters that I usually use at matches. Last month I ran my carry rig for the match as I felt I had enough dryfire practice with it. I finished 3rd, behind 2 guys running full sized pistols in OWB holsters, one of which was also running a dot.