I'm using this extruder on a prusa I2. After some work this extruder works very well, but you do need to tweak it 'a little'.
You can see what i had to do to mine here
(dutch+pics)
In short:
Solved problems:
-PLA will jam after a few minutes.
The thermal barrier is not working. The steel threaded tube between the extruder en hot end is turned down to 4mm over a length of 2mm. This does not provide a real barrier and you will heat up the entire extruder in no time, weakening the filament before it reaches the extruder. Solution is to decrease the diameter to <3mm (i've gone down to 2.3mm on a 2nd extruder).
-Idler can/will jam with high spring tension
The (very nice) spring loaded grooved idler needs a spacer between the idler bearing and the fork holding it. I used a very small/thin washer.
- Idler spring
The spring that pushes against the fork can slip off the fork when you increase the spring load. Drill a hole in the fork for the spring to fit in to.
-Filament entry/exit not in line
Use a couple of m3 washers between the extruder block and the stepper.
-Nozzle. The nozzle is very wide so it smears a lot, which makes it very hard to print small details. Reshape the nozzle so it has a smaller footprint.
Remaining problems
Filament loading. You can't easily unload the spring for loading, and the filament tends to bent in the extruder making it hard to find the little hole of the hot end.
And a remark; the extruder uses a thermocouple, not a thermistor (but you can fit a thermistor in the nozzle if you drill a small hole in it)
All in all i'm very happy with it now. I haven't had a jam/inconsistent extrusion in weeks.
