I have owned the Beretta 92fs for years, I've also had the 96 and 92G Elite II. I would recommend the CZ 75 Shadow over any of them in a heart beat. The Beretta is a beautiful gun with exceptional reliability - I've never had a jam, but the trigger is very heavy with plenty of pre-travel and over-travel and a long reset. There is not a lot you can do to improve the Beretta trigger, apart from installing the lower powered hammer spring, which brings the double action trigger pull down from awful to acceptable.
The CZs tend to have lighter triggers, even the base model, and a somewhat smaller grip, which is important for those without big paws. CZs are more likely to require replacement of parts, they are somewhat more fragile. The trigger reset is much shorter than the Beretta, allowing fast follow up shots, important in any action shooting game. The trigger reset on the CZ 75 SP01 Shadow is something to behold, on my brothers gun it is possible to fire two rounds from one deliberate trigger pull, as the trigger resets under recoil while still being pulled. Result = blablam!
Slavex, one of the moderators on this forum, made the Canadian IPSC team while shooting a Beretta, he now shoots the Shadow.
Some years ago I qualified for the Australian IPSC team (shooting the Glock 17). I am now contemplating getting back into the competitive side of things, If I do I will trade my Beretta towards a new Shadow.
TL, DR: Get the Beretta for beauty, cool factor and complete reliability. Get the CZ Shadow for accuracy, good trigger and the chance to be competitive in action shooting games.