I vote BC Forged. Like you said, you're getting a fully forged wheel for around the same price as flow formed. I've had a few sets of Vossen and many sets of BC and I would personally chose BC time and time again. Not to mention a lot of people seem to be running HF5's on the X3M so you'd be unique running RZ21 or RZ22
Tons of finishes to choose from and you pick your size/offsets.
Here's mine on RZ01
