I recently heard about the new ceramic hot ends that 2engineers have been working on. They are very simple hot ends made of ceramic, a brass nozzle and a small ptfe tube if your printing with abs. I didn't see any nozzles in 3mm so I contacted them and explained I wanted to experiment with it. He put up some 3mm nozzles and I bought two, one in .4 the other a .3.
I finally installed it on the Bumblebee II this week, and tried it without the ptfe tube for abs and of course it didn't work well at all. But when I switched to nylon it worked great. I had to experiment a little to find a good combination to print with and ended up with 240 c hot end temp, 80 c bed temp with a lite ply wooden bed.
The first round tuit came out pretty darn good, and I'm printing some door latches for my jeep and it is awesome. I'm using nylon from taulman and I'm very happy with the quality and consistency.
Picture of my jeep latch.