I did the HID (bulbs and ballasts) for both low and high on my '10 SESG.
Honestly you don't need the Highbeam. HIDs take a few seconds (probably 5 - 7 seconds) to come up to full bright. With the high beam on and allowed to come to full bright.. it is amazing.. like daylight. But having to dim them for oncoming traffic and then switch back on defeats the purpose.
Hard to describe. It's like this... driving down a dark road with low beam HID... it is bright... flip the high beam (now both bulbs are on)... and there isn't an appreciable difference at first. After a few seconds (maybe 10) the highs come up to full bright and it is amazing. Now if you switch the High beam off... you can see a huge difference.
No issue with vibration so far.
Mal
I had HID on my 04 SEEG for a few years......loved em. Put them on my wife's 09 Street Glide as soon as she got it and on my 10 SESG as soon as I got it. We have both bulbs and wouldn't be without them!

Money well spent in our opinion and well worth it.
On dim (regular) light, they do shine quite a bit further up the road than a stock headlight, as well as higher and to the sides. We did this on a mountain road, at night, no ambiant light to interfere......first hand experience. Neither have we had anybody flash their lights at us when they're coming towards us, unless we had them on bright.......and we ride side by side most of the time, so double the lighting, but we still haven't ever had that problem. At our age (60) as the night vision begins to fade, it's just money well spent.
