With my experience in my 72 bowfront I would disagree. I have prob about 100lbs of live rock in there. I have had both triggers and angels in there with very little problems. Yeah, sometimes they will graze and nip at the rock, but not to the extent that it is a problem. I would worry about angels if your rock has sponges as this is a natural food source for them. I would say go for it, however I would buy some really good "live rock" with good coloring and coraline, and then buy a bunch of the cheaper base rock. Give it time and it will be "live rock" and the coraline will spread. If you are not in a rush this will be alot cheaper.
Good luck