Are HIDs in reflector housings an annoyance when people with them are driving towards you? Yes.
Are HIDs in halogen projector housings an annoyance when people with them are driving towards you? Debatable.
Is it a good thing to do either of the above? Probably not. Argue all you want about useable light and all that. Valid issues that have been talked about by smarter people than me. What I do disapprove of is when we use the terms "dangerous" and "blinding", especially when we talk about 2008+ Subaru's with halogen projectors. The small amount of glare above the cut off is NOT bright enough to cause someone to swerve off the road or be blinded. That's complete garbage. A drop in HID kit in your 2012 wrx is not a danger to other motorists.
If you want HIDs in your halogen projectors, go for it. You are probably doing yourself a disservice, but that's your problem, not mine. It would be smarter to do a H9 setup, but its your car.