Newer vs Older

My experience with later slants is like Charrlie_S there. I had a '88 I believe, maybe last yr for the slant, 4 spd 833 OD no idea the gears this was bout '92, a super clean nice truck. It had no emissions stuff, maybe taken off or whatever. I would pull the trailer with a b body down the highways probably 60 tops, but the hard part was getting going. Clutch was weak for the load I was trying to get rolling. I drove it maybe 6 mo. and picked up another 3/4 t.
I personally would not be afraid of any slant.
I have heard people argue the virtue of forged vs cast canks eeven in big blocks, and have seen many racers run the cast crank hard with no issues. I hear same discussion with the crank in slants, but their bearings are size of the 426 hemi. Hydraulic lifter engines, I have no idea.