To me the possibility of choosing a non-stock recoil spring makes more sense with the 10mm than with just about any other auto cartridge because of the extreme spread in the power of the available loadings. Are the following correct, given that 180gr 10mm loads can vary from producing 1,000 fps up to around 1,350 fps from a 4.6" barrel? 1. The best recoil spring to consistently handle the lighter loads won't be ideal for the heavier loads. 2. The best recoil spring to consistently handle the lighter loads will, however, work for the heavier loads, but will result in the slide slamming harder/faster against the receiver. 3. The best recoil spring to consistently handle the heavier loads won't work consistently well with the lighter loads. 4. With the heavier spring and firing the heavy loads, the slide will not slam as hard against the receiver as with a lighter spring. I think all of those things are true, but I admit I am no expert and could be wrong about something. I know the slide also will close harder with the heavier spring. If those things are true (and one slide can't work ideally both for 400 ft-lb and 750 ft-lb loads), for those who only intend to fire the limited number of factory loadings available that are hotter than the .40 S&W (or handload and load hot), it makes sense to me to install a stouter spring. I have not had a single FTF/FTE with my 22-lb spring. I'm not saying anyone else should run out and get one, but it's not necessarily a preposterous concept. For me, my range time is not limited by the recoil springs I do or don't buy. It's limited by my abysmal work schedule and the amount of time I'm willing to spend away from my family during the remainder.