Full vs. Min Spool Question

Ok, so i have been wondering this for some time, but havent found an answer. What is the difference between a full and a mini spool? I am not looking to put one in, I am just curious.

A full spool is machined out of one solid piece of material. A mini spool is made to fit in an existing diff. case. It is typically a block machined to fit the appropriate axle spline, and the cross shaft that the spider gears would normally reside on.

Also, a full spool is stronger because it replaces the factory carrier, but replacing the factory carrier means paying someone to set up the gears.
Jeep on!
--Pete

For drag racing needs, a full spool will have a lower rotational mass than a mini spool so they can bring up the RPMs more quickly. I'm guessing the difference is small but when the competition is all with a few tenths of a second of each other, that small difference could be enough