I own a CZ 75B, I have friends who own or have owned other CZs (another 75B for one friend, an 85 Combat for another). I used to have a CZ 40B. For a while I had a real thing for CZs. Now, they are OK but I'd rather spend more for a SIG or BHP/FN HP, or less for a Taurus PT92. My 75B is a decent gun, mostly reliable, but has had a few bobbles. My best friend's 85Combat is at best OK. My friend who had a 75B had to send it back to the factory so many times they replaced it, and then that one had to be sent back for repair a few times. I think overall the 75B is a decent gun, but some of the internal parts are on the cheap side (and by all means, replace those springs ASAP). On the plus side, my 40B was great, and my 75B is among my most accurate pistols. They are a nice looking design (though not as much as the BHP/FN HP or any 1911).
My best friend has a Kimber 1911, I have a Charles Daly and a S&W. The Kimber and S&W have been 100% reliable (I'd consider them to be comparable quality to the Springfields). My Charles Daly has well over 10K rounds and has been a good gun, though not 100%.
Personally, I'd go with a different 9mm (if not for the low used value I'd probably sell my CZ, I only keep it since what I can get for it isn't worth it) or a 1911. Out of your options I'd go with the Mil-spec and get the .22 conversion (especially at today's prices). Don't worry about adding a new caliber- you'll end up loving the .45ACP.
