I just find that using my 5rm for 5 sets isn't possible. I'd have to use slightly lower weight which then defeats the purpose. Just can't hit the volume at 5rm sets.
Hasn't held me back
Only thing I think I can really do this sort of intensity is deadlifts. It's horrid, but the gainz are awesome.
Tried it with front squats (75% for 12 reps is not fun), and lasted for six weeks... then died.