D'oh!!
I read much more into that than I should have.
With a mouthful of crow pie, let me explain what little i know.
The clips in question are from a family of closely related suspension hardware. Some run on rails, which, upon a second look these do. Some hang from wires. Some clamp to dimension lumber (as I thought these did). Some fit IEC rail (these might). Some are tabbed for nail/screw/bolt attachment. Still others fit specific hardware applications.
The steel bit is obviously the structural part. The idea is to get that as thin as possible, thus creating the smallest cross section for conducting sound. But then, as it gets thinner, it gets weaker, right? So there's obviously a limit. Indeed, that might have been the big difference between the brands and prices. Or not. Nothing to go on, really.
The isolator is pretty ordinary stuff at this level. That is, at a project studio level. There's some really good advice hereabouts on room sizing and proportioning. Once you meet those requirements -- along with oblique walls and ceilings -- then isolator characteristics might matter and ultimately need specific callouts. As is, just call it squishy stuff.
For walls and ceilings, total up your weight. Multiply a Margin of Safety. Divide by rated capacity of the hanger/mount. That's your initial structural need. Depending on load paths, you can subtract a few here and there. The squishy stuff should have ratings for both failure (pullout, shear, compression, etc.) and freq response/transmission/rebound.
But then, a guy might have to pay for that kinda documentation, where a bargain vendor might just jam whatever rubber insert he could find. Still would have a desirable effect, far better than nothing, just more difficult to predict. Alan had a good idea, too. If it really is a concern, working with a supplier might be best. Don't know about the prices, but the product could have far more known about it and they could tell you what theirs consisted of. But again, I can't see that level of detail on a venture of this type.
Opinion-wise, I only really offered the bureaucracy thing because i have no idea what all AUZ has in store for the builder. The rest is science, except it's not because I got nothing to really go on (durometer, dimensions, testing, etc.). So i guess I was hazarding a guess there, too.
Either way, this horse is beaten
Ponder5