You used the term 'Airlite' in your title, but you then discussed the 637 Airweight, which seems to have misled some respondents. I have a 637 Airweight with the 1 7/8" barrel. You are looking at the one with the one recently made available with the 2 1/2 barrel. Good choice for power and expansion, but perhaps not for pocket carry. Your choice on that question.
I bought my 637 eight years ago, and have fired, oh, five thousand rounds from it. The first cartridges I fired, I bought along with the revolver: Cor Bon 115 +p with Sierra HPs. I fired off one load of those, and swore I would never do that again. It is now loaded with Remington +p 158gr LSWCHP, the FBI load. They are not quite as brutal as those Cor Bons, but my limit is ten. My limit with range loads is twenty. Beyond that, if I have not put a bandaid on the web between my thumb and hand, I will develop, and pop, a blister.
Another point: why a 637 instead of a 642? These are self-defense weapons, almost certainly fired within ten yards. The few times I have fired my 637 single action at targets within ten yards, I have found no benefit from it. So I don't bother practicing single action with it anymore. The 637 has a very prominent hammer; the 642's hammer is completely enclosed and out of the way. I put my thumb on my 637's hammer when practicing drawing it from an Uncle Mike's pocket holster, but this is just play-acting because I can't get a CCL in this California county. Maybe the next sheriff will be more cooperative with a retired Naval Aviator with six battle stars on his Vietnam Service Ribbon, but this one won't. But back to my point. If I had known eight years ago what I know now, I would have bought a 642.
Cordially, Jack