Originally Posted by
Christobevii3
You are looking at numbers as the same but all those little differences add up to quite a bit different frame. The BMC fits big and stretches you out a lot. If you aren't flexibile and top tall you are going to have a bad time. I know the di2 is attractive but I think you are chasing parts instead of a frame that fits. If you could fit the 54cm bmc with a longer stem and seat set back a little I'd consider it, but that 57cm is big.
It isn't so much that I'm chasing parts as I could get the BMC with the Di2 in the 54cm size too but the head tube ends up being 3cm shorter in that frame size which was spooking me a bit. The 54cm frame gets smaller than the C'dale in every measurement except reach which made me wonder if it would end up being too smallish since the 56cm Synapse did feel right on a test ride.