A lot of this dwells somewhere in the world of "good enough". Numerous options are plenty fine for normal light use and will live a very long time. OE stuff works on a different level, with some very different parameters. So just because my history tells me to "prefer" one feature does not mean that other stuff will not work.
Probably a variation on 4032 with silicon for ring groove life - Mahle and Diamond both use that in street stuff. I think Mahle may have the most advanced modeling capabilities for aftermarket stuff at this point - pretty hard to beat the resources available to an OE manufacturer just by virtue of scale. No idea how much of that gets translated to their aftermarket stuff - but if you're gonna bet... Guys like Diamond and CP probably focus most of their design efforts on the race side of their business as they should. The Diamond street parts are very nice but fairly traditional in comparison to the creativity found in the race parts.
Between their own brand, private label, and Co-Fap stuff it seems like Mahle makes most of the rings in the aftermarket at this point. Hastings has taken over the Sealed Power/Speed-Pro business. Given their market position and OE capabilities I am pretty comfortable with the move to 1.0mm-1.0mm-2.0mm ring packages and volunteered to be an early adopter, and boy does it make for a smooth turning engine on the stand. I still have customers that are worried about straying away from 5/16...
Mahle skirt coats everything, which is good insurance. They also phosphate everything which I think might be a solution looking for a problem. Some of the others have skirt coating standard, most have it as an option. Seems like a bunch of factory stuff uses it now so it can't be a bad thing to have.
In short - I personally like my current Mahle parts a lot because they are a very modern package, but in a cruiser almost anything will work OK. I prefer to stay with a forging simply because of the cost/risk/reward relationship.