Out of your three choices (Sig, CZ, EMP) I don’t think you can go wrong. I own the CZ 75B SA which is the single action version of the CZ 75B. For $800.00 I got the pistol with a trigger job and a .22 cal conversion kit. I went with the CZ for a couple of reasons. First I didn’t like the feel of the grip on the Sig, it pointed well for me, but it just “felt” wrong. I also had a hard time finding one with a manual safety. I have a personal preference for pistols with a manual safety, even if they are double action (the standard CZ 75B is DA/SA but still has a manual safety, although it is also available with a decocker). The EMP was just too expensive for me. I have a Hi-Power as my carry and just could not justify the cost of the EMP. That left me with the CZ. I chose the CZ 75B SA for two reasons, first the SA model has a slightly longer beaver tail and I felt that would give less chance of “hammer bite” and it was single action (another one of my preferences is single action pistols). As it turns out I kinda wish I had gotten the standard 75B because the SA version has an ambi thumb safety, this prevents me from putting a set of CT Laser grips on it should I want to. When I first got it I had a LOT of problems with FTF, the round would lodge just short of going fully into the chamber. I sent it back to CZ-USA and now with 700 total rounds thru it I have had no issues in the last 400. The .22 conversion kit worked 100% out of the box.
So again, I don’t think you could go wrong with any of them, they all have a good reputation. But, for the $, it is hard to beat the CZ.