Still trying to figure out what FBV profile would work best for us before we start to spend the money. But I'm not very clear on a couple of things. First, this is the part that confuses me the most. Bigger first number means larger flat area, thus better glide. However it also makes the edges sharper, thus more bite. So what gives? How do you compare 90/75 and 100/75? I'm pretty sure I got this part right: Bigger second number means "deeper cut", thus more bite - so 90/75 has more bite than 90/50, thus no as good glide. Now how do you compare 100/75vs 90/50 and 100/50 vs 90/75?