Just got finished installing this on my 2009 KTM EXC-R. The build quality of the hardware is excellent. The light is very bright and should make for great night riding. My only complaint is that the instructions are poorly produced. BD went extremely cheap here and has combined several models of bikes into one instruction manual that looks like it was printed on my home printer. You'll be jumping back and forth through the black and white photographs, wondering which apply to your bike/light setup. More detailed technical drawings would be better than the crummy black and white photos.
After spending a couple hours installing the light onto my existing shell, I think I would have rather spent the extra money for the light that includes the shell.
The light has no high/low beam. It is either all on or all off, controlled by the bike's high/low beam switch.
I got the AC power model and it really did just plug right in to the existing wiring. The electrical aspect of the install was the easiest part of everything.
I don't think you'll find a better light for your bike. A bit pricey but it is the best light for your bike.