3 questions about 6s

I really can't comment on the reason for oil pump gear failures, on the slant. I know many people have had a problem. I have been running slants since 1974, mostly 170's, and have never had a failure. I have turned my engines as high as 7200 rpm. I use a stock type replacement pump (which is high volumn compared to an OEM pump), 10-30 oil. I do some minor oiling system mods, and run full groove mains. The first year I ran a slant six, I did have some rod bearing problems, but not since then.