Originally Posted by SethAZ

The choices all look reasonable. The front and rear holes is how many spokes you'll have. Not all hubs will have all spoke-hole options, but the options available will appear when you select the hub. You'll have to decide how many front spokes and how many rear spokes, which will depend a lot on how much you weigh. I'm heavy, if you're not then my opinion won't mean much. As far as the cassettes go, my drive train is Shimano so I use Shimano parts. Cuts down on the thinking. :-) I have no idea if you'd have different spacing requirements if you tried to mix Sram cassettes with Shimano drivetrain, but you could Google that up and get your answer.