I own and shoot two calibers of Glocks: .45ACP and 10mm (G21SF and G29). I have shot .40S&W pretty extensively, in everything from Glocks to Jerichos. I think .45ACP is the softest, then .40S&W, then .45ACP+P, then 10mm. However, NONE of them are hard to control at all. The recoil of 10mm is more fun than anything. In fact, I really don't think the recoil is that much worse, but the BLAST makes it seem that way. If you shoot .45ACP then 10mm side by side, you will hear pops, then a BOOM! Also, 10mm recoil is only stout with the serious loads. If you were shooting some Winchester Silvertips, they won't feel any worse than .40S&W, even though they are more powerful. The heavy slides of the 10mm guns, combined with the fat grips really absorbs a lot of recoil. The only time 10mm recoil will be REALLY stout is if you're shooting a G29 with loads making over 700ft-lbs of energy, with a heavy recoil spring.