without going forged, a T28 is going to have to stay at very low boost to not throw a rod. and I would HIGHLY recommend a piggyback tuner (SSAFC).. i've heard that 6psi on a 28 is like 10-12 on a 25... and thats danger zone on these rods.
This only matters when not tuned correctly. I ran my 28RS at 9 pounds all day no issues. I never bent any rods, spun a bearing though but that had nothing to do with the boost.