We had one pump failure almost immediately on the stand when first testing the Kingtech engines. We then took another pump and let it run at 2.1V for a solid 8 hrs (and noted some substantial fod in the fluid), then put it back on the stand and it had delivery issues.
We then ran a second which showed the same signs after around 10hrs.
I recently tested the latest version using the same method for over 30hrs, pump performed better than when pulled out of the box with very little FOD in the fluid. Seems they have fixed the problems with wear....
This is why we packaged the Kingtech with Flightworks pumps. The new Kingtech valves have proven very reliable as well.
Todd