Hi, some of the currently active threads on here discuss recovering printheads by removing the air and refilling them with ink, and it works well. Check those for lots of details about weighing heads, checking error codes, priming, etc.
3rd-party is a totally different story because we have no idea what they do with them, nor what condition they were in before that. Refilling a printhead isn't a big deal, but the electronic and thermal nozzle portion of them can't be repaired (as far as I know), so if those were already damaged, that isn't going to change.
Last year I bought a Z3200 from somebody and it came with some 3rd-party heads that they wanted to use. Upon inspection you can see they were hp heads with the plastic logo melted off, and a new sticker added. I haven't used them, don't really plan to unless I'm desperate. No idea what ink is in them anyway.
