Stake beds have to be massive to provide enough cover for alot of fish....there just isn't enough surface area.
Look at Good Natural Cover...stumps, trees, posts, brush, etc.....that's what will hold Alot of fish....it either has to be big enough to offer ambush points and shade....or dense enough to offer protection and safety....PVC just offers the advantage of permanent cover, that you don't have to redo in a few years.
IMHO, stake beds offer neither....but they are better than nothing!