i run an oem hg on stock bolts at 76ft lbs or torque, not that great a setup but i run a k&n fipk, ddp, 3'' exhaust and a dr jonez mbc set just below fuel cut. so roughly 10-12 psi. sumthing in there my boost guage is stock so i cant really tell.
the difference is i have had my car for over 3 years and i know that it is in absoloutly perfect running order with perfect oil, coolant, timing, belts, hoses, everything is strong and i have dynoed it, taken it to the track, and made some long hard pulls on the highway without having to service anything more than the oil.
an oem hg will be fine as long as the job was done right and torqued right, user error is going to screw you up the most so make sure you know what your doing and that your putting mods on a good platform, 175k miles on a motor sounds iffy, i only have about 78k on mine so you may have different results.