nsl,
I used to own a G19, sold it, still have an old first generation G17 and several CZ's, including an SP-01. I have shot the CZ along side the G17 several times. The G17 is capable of excellent accuracy. The difference is how easy or difficult it is to achieve said accuracy. I have to work at it with the G17, whereas it seems easier with the CZ. I'm not a fan of the Glock grip angle, but it's not a big issue for me; I am not fond of the stock Glock trigger and you will never get it in the same league as a good 1911 or competition hammer equipped CZ.
The Glock has snappier recoil but it's not offensive at all. The sights are a personal thing, some like stock CZ and Glock sights, others don't. The CZ is easier to customize, the Glock has much more aftermarket support, don't confuse the two. I think variety is the spice of life, so if you can swing a G17, do it. There is a reason Glocks have become a world famous in a very short time frame.
As an aside, I may shoot my G17 3-400 rounds a year; my CZ's combined are probably in the 11-13,000 rounds per year category. I think this says a lot.