Are you talking the older Brno/Cz shotguns or the newer CZ shotguns made in Turkey. If you are talking the newer ones, there were some problems with the earlier models before 2007. Firing pins was a big thing and the occassional double fire or failure to fire. However, these problems have been dealt with and most feel they are now a pretty good gun for the money. The wood to metal fit/finish is very good and the SxS's and over/unders are built to scale. For example they do not put a 20 gauge on a 12 gauge frame. They come up for sale now and then. In fact I have a Ringneck SxS listed on the EE right now that has only been fired 15 times. I need to make room for a couple of "old classics" that I have coming.
If you are talking the older Brno/CZ shotguns, they were of exceptional quality and very nice handling. One of the guns I have coming is a very nice older Brno 16 gauge.