I installed mine ~2 weeks ago, and they have performed well. I did have problems getting both extruders exactly on the same plane. The way the instruction have you tighten the nozzle as the last step is what was causing my problem. I simply could not get both nozzles perfectly on the same plane doing it that way. I was forced to make adjustments to the entire hot end after everything was completed.

I'm sure it was me, as I am a bit OCD when it comes to some things, and really wanted those extruders exactly at the same height, which I wind up getting them darn close