I'll step forward as the owner of two extremely bright lights (Cree XML T6 based). They are for unlit country roads and the odd spot of offroad nightriding. Also great for night running sessions up the Pentlands. Bar mounted one has a diffuser lens and is dipped down so it's more like a car beam rather than a spotlight of which half goes upwards to light up nearby clouds. Second one is on the helmet and is a spotlight but it's also angled down.
Needless to say they are always off in town as I can switch to the commuter lights. They are still fairly bright (3 Watts) and are also dipped down. The handlebars get pretty silly in winter - think barends, then grips, then brake levers, then shifters, then computer, then reflector, then 2 small light mounts, then a space for the big light with the battery slung under the stem and the cabling all over the place.
I have to say I've not seen any truly dazzling lights out there yet but then the Autumn is either very young or not begun yet.
I'm going to make prediction of what the bikes along the canal will be like in a few months:
1/4 with either bright lights dipped or reasonable non-dazzling lights forward
1/4 with laser beams/miniature suns/welding torches blinding and dazzling all in their path
1/4 with barely visible minimal lights and little to no reflectives. Also counts for people with good lights with dead batteries that only produce the faintest of glows. Seen this an awful lot with people who have cable tied lights to racks so presumably the 10 seconds involved in replacing the batteries is too much to ask.
1/4 completely unlit.