Personally I don't know how much structural support things like ace wraps, elastic, and neoprene supports give. I suppose it depends on your injury/problem. Some have that little hole to help align the patella. Perhaps that helps. I suffer from knee and ankle problems myself and often wear a simple elastic fabric brace. If nothing else, it acts as a reminder to be careful. Also helps if I drop down on one knee or go to the mat.
Now as far as the heavy-duty, metal-reinforced and hinged braces go, I haven't had to wear one for years since I was recovering from my last surgery. But they really shouldn't be a problem for joint mobility in VT/WC/WT. Sure, that kind of brace is intended to restrict your knee mobility to a safe range, but then your VT/WC movements should be kept within that safe range anyway.
A greater problem might be the possible damage you could cause to your training partner with a metal-reinforced brace. On the other hand, that opens up a whole new marketing opportunity for a "Mad Max" line of tactical braces complete with studs, spikes and brackets for weapons attachment. The imagination reels with the possibilities!