This is a long complicated subject and you'd do best to look at printer reviews etc... on Cnet. However, I'll tell you what I use.
First, if you're in the States I believe that there is some Federal legislation preventing some printer companies from selling printers that print on disk due to potential copyright infringement. I read somewhere else in the 'freaks forum that this was the case.
I live in Oz...no restrictions on label-capable printers.

My printer is a Canon Pixma Ip3000 ( superceded now ) which has a special tray for inserting DVDs /CDs. It comes with simple and effective software that allows for adjustment of prints to account for hub size variability.

The prints are matte but richly colorful. Manufacturers such as Maxdata are now making blanks that have a luminescent 3D sheen when printed upon.

The prints are smudge and water-proof 5 minutes after spitting out of the printer.

Prints take about 45 seconds per disk.

I have never heard of a printer that puts a "gloss-coating", as you put it, on a disk.

In Oz you can freely purchase Chinese cartridges for about 1/4 of the price of the originals, sometimes less. In my experience, they work just fine. At our computer markets I have paid as little as AUS$5 for a single cartridge. Never had one fail yet.

Hope this helps.