I too alternate them, up at boxes, and down everywhere else. But if worried about someone swinging around on your pipe work like tarzan, use rigid pipe, with 2-hole straps with 1/4"/20's epoxy'ed a few inches into the wall. (or those hilti style "toggler" bolts)

Or maluable iron 1-hole straps with backing clips also with 1/4"/20's.


Mark Heller
"Well - I oughta....." -Jackie Gleason