A big negative for me was when I printed 900 pages of text documents - apparently the document pdf was encoded as color, and the print job completely depleted all my starter toners.

The first reason is that Brother is engaged in a very dubious practice regarding toner management.

This default will keep you from accidentally printing a bunch of color pages that would use the more expensive color toner.

Toner was a concern at over $600 for a set of

The second part of the issue, specifically the excessive toner wastage, has to do with the cycling of internal cartridge components.

Yes, the toners for this printer are very expensive.

UI is overly complicated and not all features seem to work; toner-thirsty; small paper tray; Tech Support abilities; expensive toner; unable to use all functions of the printer

Also, the toner smears when you touch a printed page, and leaves residue on the back of the page after it.

Out of the box, we have the error code telling us that a non-genuine toner cartridge was installed

I learned that this unit needs to be connected directly to the outlet and not to a multiple outlet extension cord because it needs to draw max juice to warm its toner and jump in and out of sleep mode.