My W2 416 is 10:1 with a 4" Eagle crank. It has a big roller in it and if I didn't already have that 4" crank I think a 4.125 would have been better for it for all the reasons Billy mentioned.

I haven't used a BPE kit but they would for sure be on my list of vendors if I were to do another rotating assembly. I do not know what Molnar offers for rotating assemblies but I do know his customer service is good. We have his Rods in the 416 and they are a nice piece.