What evidence do you have of this claim? Any road tests where a reputable source used aftermarket HIDs and tested them to see if the light was scattered? Of course they're not the "same", that goes without saying. If they were the same, they'd be the...same.
Not true. I have low and high beams and they work quite well. The bulb base has a strong magnet which pulls the bulb backwards when you activate the high beams, and thus the light is aimed upwards. I was skeptical of this at first, but it seems to work well.
Are you just quoting something you read somewhere? I've had multiple cars with HIDs and not all of them were "unbeatable". My 2001 Maxima (with retrofitted 2002 OEM Maxima HIDs) were pretty good. My 2007 Infiniti M45 had awful HIDs. My 2009 Jaguar XF had phenomenal HIDs. My 2009 Cadillac CTS-V had mediocre HIDs.
Right now I have my 2008 F150 with 5000K HIDs and they are FAR better for night time visibility than the stock halogens. My 2006 Mustang also has aftermarket 5000K HIDs and they are just as good. I get maybe one or two people that flash their high beams at me a month, which is about average or less than average compared to other cars I've owned (all stock, some halogen and some HID). Most of that flashing comes when I am cresting a hill and the beams shine directly into the face of the oncoming driver, which has happened many times before even with OEM lighting.
My eyes are in my head, so yes...the gain is definitely in my head.
I'm sorry you purchased bad HIDs or possibly didn't have them set up correctly. I too have had 6000K and thought the output was awful. For my eyes, 5000K lights up the road the best and gives me the most optimal view ahead. 6000K is just too blue for me, and I couldn't even tell the lights were on some times.
I know you're trying to contribute, which you've done extremely respectfully, but it seems as if your negative experiences with aftermarket HIDs has been due to poor purchasing choices (namely, 6000K bulbs), claims with no basis in fact (scatter), erroneous information (no high beams), and a false reliance on "popular opinion" (unbeatable output).
No disrespect, just pointing out some errors in your information.
Tony