Just my opinion, but you buy a commander size gun because they are easier to carry. Getting one with a steel frame is kind of a waste. You might as well get the full size for the amount of weight it saves you. People will argue that the steel frame holds up better. If you shoot your carry weapon enough to wear out the aluminum frame, you are either practicing a bunch, or you need to change your life style to avoid all of those gun fights. It takes a long time to shoot 20K+ rounds through a 1911. I reload and spend about $.12 a round. That's $2400.00 in ammo to "wear out" the aluminum frame. I still haven't found anyone who has done it, but 20K seems to be the number the "experts" are using. My Pro CDP is a joy to carry. You don't even notice it on your hip.
As for recoil, I notice a little difference between my full size, all steel 1911 and my Pro CDP when slow firing at the range. However, when I shoot IDPA and I am concentrating on the task at hand, I don't even notice the recoil. People shouldn't judge the recoil of their defense gun when shooting it as a target pistol. If you want to shoot a target pistol that won't hurt your hand, buy a .22. They're a lot of fun.
I have the Pro Carry in alloy and in steel frames. I notice a big difference between the two. The alloy tends to twist more in my hand and the recoil impulse is sharper. After 100 rounds with each gun I can feel the difference -- it's more tiring to shoot the alloy frame. There is a weight difference, but it seems less noticeable because of the weight of a loaded .45 mag. Some of the perception of weight changes if you use a good quality holster. The bottom line is that if you plan to shoot a lot you're better off with the steel frame. Even if the alloy frame holds up for 20k+ rounds the slide to frame fit will get sloppier faster.
I bought a Kimber sts Pro Carry for the reduced size and weight.Mainly for carry comfort.After 10 or so hours You'll feel it.I don't shoot My carry gun enough to worry about durability.I shoot a steel gun for practice instead.As far as recoil ,I don't even notice the difference.This gun is well ballanced and accurate.Mastermind has it covered quite well.tom.