While IMHO i am on the fence on this subject I tend to lean towards rsilvers side and heres why.... HPT/MPI does keep a company honest and at least set some sort of minimum bar. However on that note I think the likes of DD/Knights/BCM/ECT companies that have stood the true test of end user critique... Which at the end of the day really really matters. Not so much from first time AR owners that swear by their deltons (although Delton serves its purpose as well) but by veteran owners with multiples. If the majority says that DD/Whatever Bolts are the shit because they have had a few they probably are right HPT/MPI or not. I have no engineering experience tho so my opinion may not matter much. I do know as I have ok welding experience that we have come along way since Mil Spec metalurgical standards.