In the last few days I've rebuilt my primary printer using up to date i3 parts and the newer box frame. I'm happy with it.
I installed an older JHead because it has a 0.35mm nozzle which I wanted to go back to and try, but it didn't work out. It's an old design (Mark III I think), and it has the squared off nozzle profile - this catches on the printed object as it's travelling and once the parts get 15mm or so high, the head pulls the parts off the bed.
So I went back to the 0.5mm Mk V head.
I went back to direct drive too. The Bowden is kind of a pain in the butt in several respects and the only plus was doing 2 color printing, and apart from printing one test, I haven't had any call to actually use it.