I own seven CZ's (75 SA, two 75 B's, two 75 B Compacts, Rami, Kadet) and three Glocks, all in 9mm. The CZ's are beautiful guns and fit my hand better than any other semi-auto. Their DA triggers are pretty stiff and long, but I always carry them cocked and locked and never shoot DA. The SA pulls have some take-up, but otherwise they're excellent and very easy to shoot quickly and accurately. All of mine are reliable and accurate; I love shooting them.
The Glocks (19, 26, 34) are blocky but they point more accurately than any guns I've tried. They have excellent sights (easier to pick up fast than those on the CZ's or any Smith revolver), are totally reliable, and have the best trigger pulls this side of a good 1911. Glocks and CZ's usually have similar accuracy in my hands, although the CZ 75 SA (single action only) has a slight edge most of the time. My Glock 34 is a marvelous piece of work in every regard - costs half what a top 1911 would and gives away nothing in terms of trigger pull and quick proficiency at the range.
The upshot? I love both brands; they got me out of revolvers after years of buying, trying and rejecting most of the semi-autos on the market. I'd be completely comfortable with either for defense or competition, although the remarkable light weight of the Glock 19 or 26 makes them the best carry guns anywhere.
If absolutely pressed to pick one, I'd go with a CZ 75, either full size or Compact, mostly on looks (and you can spruce them up further by purchasing beautiful wood grips). For function and all-round shootability, however, you can't beat a Glock 9mm.
So I hope I'm never pressed to pick one over the other.