I have done both ink refills and just starting to do laser toner refills.
The OEM ink cartridges are just way too expensive to buy retail (unless it is for work)--but for home it is the only way to do any real color printing. I have been refilling a Cannon ink-jet type printer and it works OK... The price is low and the cartridges last OK (but I do have to buy a new one every so often).
However, in the end, even refilling the ink cartridges is a pain. I have pretty much chosen to put the printer away and just use laser instead. Now I can print 3-6,000 pages without having to touch the printer. The ink jet seemed to be just 100's before I was refilling an ink container or trying to clean a print head.
If I needed cheap color, before I bought a printer I would go to a web site like
www.weink.com (I have bought a toner refill kit from them, the first time, a few weeks ago and they shipped it quickly) and look at these types of external continuous feed inking systems. And, once I found a system I liked, buy the printer brand/model to fit it. I saw these types of systems used all over in Taipei.
Regarding refilling Toner Cartridges... I just purchased a Brother HL 5170DN about a month ago and have already put close to 13,000 pages through it using one 3,500 page toner cartridge (this is the small one that comes with the printer--the big one prints about 6,500 pages) and I have been refilling it myself.
The first time I refilled it take a bit of mechanical fumbling around to figure out the instructions and trying to keep everything clean (free of grease and black toner dust)... Which is kind of hard considering that the gears are covered with grease and you have to dump out about 80 grams of old toner on your first refill (they recommend dumping the OEM toner out so that it does not cause problems with the refill toner's slightly differing chemistry).
Other than doing it outside and taking my time with a few hand tools and a lot of paper towels, it went OK. I have since refilled the cartridge 3 more times and the printing is 100% perfect. And the subsequent refills, I just top off the toner (don't dump any) and it only takes a couple minutes to pull the plug and dump (by weight) the refill toner in. The cartridge is supposed to last about 4 refills before needing to be replaced (I don't know if this is 4 x 3,500 pages or 4 x 6,500 of the larger toner cart-- but it is doing real well so far).
I am down to about $28 for toner for 10-12,000 pages of printing (excluding other costs). Plus, this printer has duplexing, so that I am using half the paper too.
There are expensive consumables too—like a new toner cartridge ($70) and the drum that has to be replaced every 20,000 pages or so ($120 new) or the fuser (after 60-70,000 pages--don't know its price). But I do like being able to print thousands of pages without stopping to refill ink or clean a cartridge.
-Bill