Every time I've seen compatibles the blacks have been lighter than official, that includes ink and toner.
So I always religiously stuck with HP and their own inks, until I realised I was printing so infrequently the dyes were going bad or the nozzles clogging, so I moved to laser in October 2013.
Sure official toner is expensive, but the starter black lasted about six years (I could have gotten longer out of it but it was started to get patchy) with the colours reporting as very low but only just starting to occasionally show in print quality.
There's also the fact you can generally get away with cheaper paper on laser and as my mum prints a lot of postage labels, its clearer and no chance of running if it gets wet. I do hate the environmental impact of toner though, plus its rather dangerous if you spill it which few people seem to realise. (another reason NOT to use third-party)