One of the firearms I received when the sister-in-law's husband passed (brother-in-law) was a FN Hi-Power in 40 S&W. I never did and still don't have a need for a 40. To me it's a solution looking for problem. Any way, the first thing was to eliminate the magazine disconnect, and then have a fiber optic front sight installed. The metal frame of the front sight failed, so it's back with the 'smith getting a set of Heinie sights installed. I have the same brand and style on a 30 year old Hi-Power 9mm and a Kimber 1911 45.
The most available bullet for the 40 is 180 grains. I've been loading 185 or 200 grain bullets in the 45. The velocities are close to the same and therefore the felt recoil is about the same.
Another pistol given is a 45 colt single action revolver. Until recently I haven't shot it. I ran about 40 rounds through it and thought it was ok, but won't shoot it very often. I just don't like the grip style or angle. I suppose that's because I've shot 1911s so much.