From your big bore handguns of course. I shoot my hunting loads because they are the most accurate. I have never found a light load as good.
Then I have taught many to shoot and found going from a .22 to a .38 and a .357 to the .44 did not work. Each step had the students brain yell "RECOIL." I found to start BIG first with proper instruction is better. Once they see it is not that bad and get used to it, they shoot better with any gun.
Friends son was here and I was shooting my BFR in .500 JRH. He was afraid of it until I showed it could be shot with one hand. He took it and soon was busting pop cans at 50 every shot. He then took his fathers .454 Freedom and was hitting cans at 100 off hand. Now he does not even care for a .44 mag.
I have seen so many get better from reverse training then from starting with baby guns.
Since my revolvers are for hunting it is best to shoot those loads even if at jugs of water.
Cost some will say but most are a dime a shot to a max of 13 cents. I see Garret loads are $2 a shot. You can shoot a 50 BMG for that.