TAZ 5 New Top Mount Spool Holder

I am really loving this design I picked off of thingiverse. Locks on tight without screws. Recovered about 8-10 inches on my desktop. Does anyone know why the TAZ is designed with a side mount rather than top mount. Is there issues with the spool being on top? Seems more practical.

Thanks,
Chris

Nice! I need one of those for the five pound spools I use.