This story gets bubbled up to the surface every few Years doesn't it... My current family workhorse is a Brother MFC-620N, few Years old now, and other than one set of original replacement inks (from Argos in a special offer) I have used Tesco replacement cartridges (no problems), and both Tesco and ASDA ink refills (a little fiddly and needs care to avoid spillages but certainly work OK). In terms of quality, the originals are *very* slightly better than compatible/refilling - but not enough to warrant the increased cost.
I have needed to replace the waste sponges from a donor 420N but it's still going strong and used on a daily basis for colour and B/W.
I have a Canon 4600 which I use exclusively to print photoraphs and DVD labels, and so far have only needed to buy one set of inks - they *were* original because the unit was only 6 Months old at the time - and a recent check of prices in the high street shows little saving over compatibles... presumably this model isn't popular enough for the really cheapies!
High volume printing is done on a Panasonic B&W laser which I have managed to buy a small stock of original toner cartridges on Ebay a Year or two ago!
The only clogged print head I have had was with a Canon ip500 which had been standing unused for many Months - yes it had compatible cartidges in it, but it was the non-use that killed it.
In general, I would imagine the majoriy of problems people have is from using the cheapest compatibles they can find, which oddly enough are probably not remanufactured all that well!