Some members have done it and they do like it. However, the design of the reflective housing for the high beam doesn't project the light as well on to the road and, from what I've read, the HID high beam isn't as impressive a difference as the low beam. And it's not totally because of the projector vs. composite difference between the low and high beam, the highs just have a very small surface area to reflect against.
Plus, between the HID lows/fogs, I get flashed too often to wait for the high beam to warm up to signal they aren't on to oncoming drivers. I'm about ready to start keeping a 3 million candle power spotlight on the passenger seat
