I've had them both. Reliability and performance (for me) are very close. I now run the Hella's on Garauld's brackets.
I crashed my bike and broke one of the PIAA's. For the price difference, it wasn't worth it to me so I went with Garauld's light & bracket package that was available at the time.
I run the Hella FF50's on Garauld's brackets too and am happy with them. The feedback from the reflective items on the road is almost enough to hurt my eyes
If you have the Gen 2, the installation doesn't require any drilling, as the air intake vents lead straight to where you want to run the wires.