I too was looking at mills, I was wondering how much work justifies a mill? If you have a scanner and milling centers are fighting for the business you can get them back super fast, is it worth having your own mill?
depends on a number of factors.
1. how slipshod is their quality? do you experience many remakes? are their shades inconsistent or consistently off?
2. are you willing to do the legwork to get better shades, and spend more money on zirconia than you ever have ?
3. do you expect the process of CAM and sintering to be plug-and-play ?
when i first began milling i was given the YZ dipping solution and 0 instructions. naturally everything came out dark piss yellow. i also had a milling machine that was of fair quality but again very little in the way of instruction.
this is the worst case scenario; you buy something at good price and end up with a thing you have no idea how to use and takes months to learn properly.
no doubt this will *not* be the case for you but be prepared. every time you change zirconia brands you change the outcome of the shading process.
there are lots of tabletop average quality stuff out there. most of it will come with at least a hotline to have questions answered, and a 1-3 day training session on the basic operations of the unit.
but you gotta really have some kinda bug up your butt about the milling center currently supplying you. otherwise i'd just continue to outsource.