I'm a CZ fanboy, too, and have had a large number of different models over the years. I still have an 85 Combat that has been slightly tuned, a custom AT-84s, and am shooting a Sphinx SDP on loan from the importer. They're all great guns and the last two cited are based closely upon the CZ pattern. (I've had a number of Witnesses, too, and like them as well.)
The original poster was comparing the full-size 75B to the compact SR9c -- two different types of guns. In terms of size and weight, not performance or quality, comparing the full-size 75B to the SR9c is like comparing the Chevy Impala to the Chevy Cruz. A better comparison might be the "full-size" SR9 to the compact CZ 75 PCR, or comparing the even more-compact CZ (the RAMI) to the SR9c.
In the following paragraphs I take it a bit farther off track, and compare a different CZ and a different Ruger, but two guns that are more evenly matched.
I have an early SR9 which I like a lot. It had the older trigger, which wasn't great -- but I improved it with the Ghost trigger kit. The trigger is still a bit heavier than I like, but it is a clean/crisp trigger. The gun is very accurate. The later SR9cs and new SR9s have a much-improved trigger over what I had with my original SR9.
I have had several a CZ 75 Compacts (the capital C denoting the steel-framed version of the compact line). They were good guns, but almost as heavy as the full-size gun and I saw little advantage over the full-size gun. I've never owned a compact (alloy-framed, with decocker) such as the P-01 or PCR), but do like their lighter weight. I always thought that a safety-equipped alloy gun would be the best combo, and they are now available, through the CZ Custom Shop -- or in some models equipped with the Omega trigger system.
When you compare the SR9 to the PCR you see that they are quite similar. I used their respective websites for the details but the CZ site's info is incomplete and that forces you to use their manuals -- which are in centimeters. (I used a web converter, but some of the conversions from centimeters to inches may be a little off.) In the following display, I've compared the FULL SIZE SR9 to the COMPACT PCR, but as you can see, there is only a little difference in size. The SR9C, not compared, is even smaller and lighter than the PCR. The SR9 is smaller than the full-size CZ75B.
Weight:...........PCR=25.4 oz......vs......SR9=26.5
Capacity:.........PCR=14 rounds...vs.....SR9=17 rounds.
Height:............PCR=5.03".........vs......SR9=5.5"
Barrel length:....PCR=3.62".........vs......SR9=4.14"
Overall Length:..PCR=7.24".........vs......SR9=7.5"
The SR9 is very close in size a to the PCR and weighs only an ounce more; it's 1/4" longer but with a barrel that is 1/2" longer. The SR9c is even smaller than the PCR. The PCR, weighs 2 oz. less, is .5" shorter overall, with a barrel that is only .2" of shorter.
What's the big difference? Both companies have exceptional customer service and support. The PCR has a metal frame, is hammer-fired and has a decocker. The SR9 (or SR9c) is poly-framed, with safety, and is striker-fired. Those differences seem to be the most compelling. If you like metal frames and hammers, you'll likely go the CZ compact route. If you like poly frames and strikers, you'll likely go the Ruger SR9/SR9c route. If you have no preferences, you might be lured by the Ruger's slightly lower costs. Buying used, it's not a big issue, either way.
I like both, but would probably find myself carrying the SR9 (or SR9c) more often -- mostly because I don't like the differences between the first and second trigger pulls on the decocker-equipped hammer-fired guns. (That's a very subjective thing and many folks don't care about the issue.) The Rugers also have fully adjustable sights, a plus to some, but meaningless to others. If you want a more-compact guns, then the CZ RAMI and the SR9C are the guns to compare.
The new CZ P-07 might be a better match to the SR9 or SR9c, and it seems to be a fine weapon. I have no experience with that model, yet -- and THAT was not the subject of this discussion.