If you do your own work on your guns you'll find CZ's are very easy to get parts for. Check out CZ USA or CZ Custom or Cajun Gun Works.
You can buy any factory part except the plastic frames for the P07/P09. The P07 and P09 do not have the metal frame rails molded into them like some plastic framed guns - so you can buy, and replace those if you ever found it necessary.
I've not yet had anything break on my P07 or P09 but I've bought many of the small pins and springs and spare ejectors, extractors, etc.
So far my P07 and P09's are as reliable as my Glock and XDM handguns and more reliable than my M&P handguns.
So far my P07 and P09's are more accurate than my Glock, XDM and M&P handguns.
Yes, magazines cost more. If you get a P07 and want higher capacity magazines think about using the P09 magazines. My .40 S&W P07 magazines hold 12 rounds each. The .40 S&W P09 magazines hold 15 rounds. I don't buy P07 mags. these days.
I've heard good things about CZ's customer service but I haven't had to use it yet.