I used it in a Commercial Briggs 16 HP VanGuard V-Twin and sent in a couple samples to Blackstone.
The engine is 20 years old and I used to use Mobil-1 15W-50 RedCap as is was a 1400 ppm ZDDP product vs GoldCap and SilverCap which are now 1200 ppm ZDDP products.
I like V-Twin with it's 1600 ppm ZDDP levels.
Long story short.... the M-1 V-Twin samples all came back with zero for copper/iron/lead etc...wear metals. Amazing! About 100 hour changes.
I also like Motul 300V 15W-50 or 5W-50 with high ZDDP and Moly along with the fact the 300V is a double synthetic GRP V....though priced at $15.00/qt.
Anways...the M-1 10w40 mx4t is a good choice as well with 1600 ppm ZDDP.
Amsoil's ASE with 1150 PPM ZDDp SAE 30 is another great choice.
BUT......nothing beats M-1 V-Twin.....I mean 1600 ppm ZDDP and a very beefy synthetic base,,,,
Outstanding choices!