I totally forgot the high beam/low beam question... I was too distracted by the adorable puppy.
I ride with mine on during the day, all the time, occasionally I get "flashed" by oncoming cars, but whatever, in NY I'm pretty sure it's a law that you have to have your high beam on during the day if you are on a 2-wheel vehicle.
I keep it on at night unless I am very close behind someone (close enough that I can use their headlights for visibility of the road), or if there is oncoming traffic. Even when there is oncoming I sometimes "forget" to turn my high beam off, and sometimes I'm "flashed" for it, sometimes I'm not... sometime's I'm flashed for JUST my low beam... so... yeah.
I have a 2012 170i with the stock headlight, and it is extremely bright, both high and low beam... Eventually I will upgrade it to something snazzier, but it seems more than adequate for now.
Also, I am quite small in comparison to Skootz, at 5' 1.75" and ~130#, and the little mirrors work well for me too. I think it's all about getting the angles exactly right for your body style. I can see both lanes behind me and a decent amount of what would be diagonally behind/next to me on either side, from both mirrors very easily. I'm sure you can find some nice tear drop mirrors to replace them though. I know someone posted some off of a Yamaha that should fit the Buddy... for someone else who was asking about replacements... in another thread... ?
EDIT: Yup, this one!
topic20463.html
No power in the 'verse can stop me.