My first was a printrbot simple metal I put togather from a box o parts. it was decent enough for 2014. It got a few factory (and non-factory) mods and replacement parts put into it, but what killed it was the hot end dying, combined with printrbot as a company going casters up.
I tried to refurbish a flashforge dreamer, but hit the wall of "for the amount of money I need to sink into it for replacement parts, I can buy a new one" so I did. my CR-6 has been more or less solid for me, Although the Community firmware for it blows the factory firmware out of the water in terms of features and usability. (that is one of two mods I've done, the second was hard-wiring a power cord to the supply and trashing the power entrance that blew out on me and is listed as a "known issue" with the first-gen run of that model...)