In reply to winhill:
My review hasn't actually been published yet so I'm not sure how you know that; however, somewhat psychically you are right - I didn't include this within my review!
Awesome Walls had no problem whatsoever, if anything they were all keen to see how it worked (and were impressed by the results). Whilst I'm sure the response will vary from wall to wall, I would be surprised at any establishment having an issue with the use of a device that is likely to make the belaying process safer and easier. Still, exceptions do occur. In the event of this happening a quick chat would most likely resolve the problem. If not it's back to the ballast bags!
In terms of placement, I clipped it on top of the perma-draw, which seemed to work fine. There's certainly no need to remove the perma-draw (which I think walls would take an exception to) as there's plenty of space within the bolt for both.
Hope that answers your questions.