I'll tend to agree with the crowd here except for the hardened shaft. It's a preference call, but I had a couple of experiences that make me lean that way. Oil pump failures are few and far between.. Most people have never seen one. I've had two. From my observation, that little skinny drive shaft is engineered to be the weak link. I. E. - in one instance i had a stock drive rod. It twisted off when the pump locked up and didn't damage anything else. I lost oil pressure, killed it, tore it down, fixed it. The hardened drive shaft tore up all kinds of crap when that pump failed. Distributor and cam gears both ruined. Lots of carnage. So, just my .02... I run standard pumps and standard shafts in all of my engines after those episodes.