as far as i’m aware 40t are actually better… i don’t have graphs or proof, but i have good sources that tell me p42 actually heat up way to fast, especially in a power hungry board like a mtb. Companies actually make small revisions without saying, as you can see mooch does second tests after a year or two and that’s not coincidence. 40t used to be quite bad actually, they were first rated at 20A but revisions made them much better. p42 have had few revivions and the only way they are better that 40t is because molicell actually push them to the limit. i have a 12s6p p42a going into my board… i wish i had gone with 40t tbh even though i havn’t tested either yet/
i don’t think i’ll be dissapointed but i’m scared to see how hot they get, especially in summer and also their lifespan over the years. I would say 40t is better but again i have to physical proof, only some secret sources
that’s my 2c 
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