How well does it wear with carry?
I don't know, as I haven't carried any of the gun's I've rust blued. I can tell you, though, that in the process of researching, it was pretty universally agreed that rust bluing produced the toughest and most wear resistant of all the 'true' blue finishes. Way beyond cold blue, and better than hot salt blue - just slightly south of parkerizing, though.
The CZ82 I did earlier this year, though I don't carry it, has been to the range several times and has had several hundred rounds through it and shows no wear at all - none. It's a straight blowback design, so the recoil spring surrounds the barrel and this is usually the first place that wear occurs on these guns. So far, the barrel is still pristine. Just anecdotal, I know, but it's all the data I have at the moment.
My personal opinion: It will wear as well, if not better than any factory blue finish.