M1 is not nearly as good as it used to be. For of the shelf oil, Castrol syntec is great, pennzoil/QS as well. For a premium Amsoil, valvoline, etc. I stll cant bring myself to trust RP oil.....no problems with gear lube, etc. but we lost to many engines in the days they were title sponsor of some of the IHRA classes.
The biggest issue is using convemtional or a dexos approvend blend. After breakin, get a good full syn in and never use a conventioanl. It is a sure recipe for failure (I know of no one doing more with the LLT & LFX engines than RX). Any one that should know better and still uses conventional is just asking for failure.
And yes, the new chains are improved, but not by alot. It is also critical that you check oil levels regularly as these do NOT have low oil indicators, so you need to monitor it every few fuel fuel ups.