Bike Question: How important is the hub?

The components of the hub are (rear specifically since that is where the big differences will be):

1) The hub body (the shiny big part that holds everything together) which can either be aluminum, carbon, or a combination of the two.  This holds all the guts together and is where the spoke head will thread through.

2) The bearings - pressed sealed steel units (self contained bearings and lube), free bearings (ones you used to have to pack and arrange yourself - rarely see those in anything worth a dime anymore), and ceramic sealed units.  Ceramic are the "smoothest" of them, and as such the most costly.

3) Freehub - this is the part the cassette goes on.  They also vary from steel to aluminum to titanium.  Within these are a pawl/ratchet system that gives you your freewheel affect.

4) Axle - chromoloy, aluminum or titanium.  This is the part that takes all the abuse and the majority of the loads on the wheel.

Any combination of those things can result in a lighter, more expensive, smoother wheel rotation.  The top level would be some sort of carbon/ti combination with ceramic bearings.  You are talking $500+ for a kick azz top level rear hub.

So there can be a major difference in the weight and rolling capability of the hub and is where a big chunk of change can take place.

In the Flashpoint vs Zipp line, unless things have changed the Flashpoints still do not use the dimpling even though they might have the same profile.

You rock, Daremo.  I now know what a hub is.  Now I just have to find out which kind specifically is used on the Flashpoint and if it is that much inferior to the Zipp 404 hub. 

Thanks again for an outstanding and informative response.

+1 to everything Daremo said.

The Zipp hubs are considered to be very good, and the FPs maybe a step down. However, the hubs on the FP's are still very good. I would SERIOUSLY doubt you would notice any difference between the two, except maybe at slower speeds.

The 404's can be used as an everyday wheelset, whereas the FP60's will probably be race only for most people. Im not sure if that is a consideration for you or not? If you are looking at race only wheels, im wondering why you wouldnt be leaning toward a deeper profile spoked rim, H3s, or a disc/cover for the rear? 

When you've had to take apart and (attempt to) rebuild a Sturmy Archer internal 3 speed coaster brake hub a few times for customers that were too cheap to just buy a new wheel you learn ALL the ins and outs of hubs.   (I also custom built wheels with everything from the cheapo stuff to the $500+ hubs I mentioned - that was some of the more enjoyable work I did in shops).

Glad I could help!