I own two Steyrs (an M40 and my EDC an S40 ... both are first generation "pre A1" pistols). They're great guns, probably one of the best designed and built polymer pistols out there.
But the CZ is a classic.
If you're planning on CCWing this piece, get the Steyr.
But then again, if you're planning on getting both, get the Steyr now. Steyr is in limbo right now in the US market so unless they get their importer situation sorted out there won't be any more new ones coming into the US (
Steyr Arms in Alabama still does the warranty work on them ... and they do good work with excellent customer service).
These guys have a lot of CZ75s on Gunbroker (couldn't find a link to their actual site so I'm assuming they don't have one). I've bought from them in the past and they're good folk.
Dunno if CDNN has the CZs too, if they do they'll likely have a good price. Download their latest catalog
here (you'll have to call for prices on handguns).
As for which gun is better, you can't go wrong with either.