Ive been running a 1/2 x 1/8 bmx chain for about about 400km with a few good hills
i had to grind the front sprocket to make it narrower and the chain is probably getting a bit stretched (hav'nt looked at it for a while) but is definetly Very smooth and better acceleration compared to the 415 i didn't know about the #40 #41
but i'll check em out