CZ-75's are nice guns for their class and price point. They have been widely copied (Israel's Jericho / Baby Eagle, Tangfolio TZ-75, EAA Witness, etc.) and that is usually a pretty good indicator as to how good the design is. -I believe Armalite also has a version of it.
One of the neat things about them is that they have the rails for their slide reversed. Instead of the slide grabbing the frame from the outside, it actually sits inside of the frame. Many shooters feel that this allows the gun to cycle more smoothly and in turn provides greater accuracy.
CZ has a bunch of variants so whether it is a good deal depends on whether the variant you have the opportunity to buy is one that provides the features you want.
Do it! The CZ is one of the straightest shooting autos you'll find. $400 is a good price. If you don't want to go 9mm for some reason, the Witness by Tanfoglio is the CZ-75, but you can get it in .45 and 10mm.