I've spent some time behind the trigger of a CZ-75B, CZ-97B, P220, P226, and P229. There are a few things I've noticed:
(1) Sig's generally have a bore axis that's way too high for me...like the H&K USP series and S&W's line of autopistols. That means more muzzle flip than necessary. In contrast, the CZ-75B and 97B place your hand WAY up on the backstrap, so the bore axis is nice and low. For me, that means much quicker follow-up shots and much more comfort.
(2) The shape and size of the grips is very different. You just have to feel both and see which one fits you better. For me, the CZ's just fit my hand better. When you also factor in the lower bore axis, that makes for some very comfortable shooting.
(3) Most Sigs are still DA/SA whereas most CZ's can be carried safely in Condition One (i.e., "cocked and locked"). If you're the kind of person that's comfortable with Browning's 1911 and P-35 platforms, you'll probably be more comfortable with a CZ.
(4) If you do choose to carry with the hammer down, then the CZ presents a problem. Sig DA/SA autos have a decocking lever that safely drops the hammer. CZ's need to be manually decocked. Personally, I'm not comfortable lowering the hammer on a chambered round: there's just too much that can go wrong and lead to a N.D. If I were to carry my CZ-97B, I would only carry Condition One.
(5) In my experience, the quality of the trigger, fit, and finish is roughly comparable. Personally, I do NOT see the Sig as being head and shoulders above the CZ in terms of quality. So, it would be hard for me to justify the price difference on that basis alone.
(6) In my experience, accuracy is comparable. In fact, in my hands, the CZ-75B and CZ-97B have been more accurate than comparable Sigs. Again, it would be hard for me to justify the price difference on that basis alone.
(7) In this country, Sigs still have better aftermarket support. You'll find more gunsmiths that know how to work on them. You'll find more holster and accessory makers that support Sigs. You'll find more sources for parts and mags. To my mind, this is the only real downside of the CZ platform. For example, I've been shopping around for new grips and a holster for my 97B. Basically, there are only 1-2 sources for these products. So, if I want a custom holster or set of grip panels, I'll need to physically ship my gun out of state to the maker (with all the hassles that entails). The 75B has better support than the 97B...but it's still not as good as it would be for a Sig.
Anyway, these are my thoughts. Hope you found them useful! Feel free to PM me if you have specific questions.