I installed a set of those HID retrofits everybody hates and am perfectly happy with it. See this thread:
Anyone have hyper white or Hid kit for their boxster?
The light pattern have not changed at all, just look at the pictures (Driver side is supposed to be aimed lowed by US regulations). But the night visibility improved drammatically...not bad for $150.
No tickets or light falshed at me yet. My only complaint is the occasional battery light that comes on when you turn the key almost same time as turning on headlights, but it goes away after pushing spoiler button (Dont ask me how that is related, or how I even found it)
My guess is that blinding light is from the missadjusted headlight, or people who install the more powerfull off-road kit and drive it on the streets.
Just my 2 cents