is this true about a 350 sbc vs a sbm

this guy come in to the store last night asking about a mini spool for a 8.5 gm axle. so i hop on my oriellys computer and i cant find one, i call my tech and while waiting for tech support i ask the guy y? he said to lock up the rear end and looks at me like im a dumbass, and i asked him y a mini style spool? and he says doesnt wanna deal with c clips and that he spent so much money on chromoly axles cause his chebbie makes 475 at the rear wheels blah blah. now ive heard his truck and it does NOT sound like its got 500 or more. And then he had to rub it in cause he seen my demon hat, and says my chebbie got more ponies than any mopar can make and last longer and this is when i got pissed cause im pretty sure mr pettyblue has a 408 dart that makes 500 easy, and 7172 duster has a 340 with 600 if i recall, among others here who make as much or more.

now my question is, is this guy right? will a 350 last longer with 500 hores than a sbm? or is this guys head shoved so fat up his own *** that he can see his tonsils?

His claim isn't worth worrying about - he sounds like the typical idiot who thinks his shitbox is much faster than it really is.