Right, I'd forgotten to list that. Thanks.
A. Commuting. On roads or on concrete bike paths.
B. I guess my biggest constraint is what I listed in the OP: able to cast a long enough beam to travel fast on the road and not be surprised by obstacles and able to last an hour or so. But in some searching I'm seeing plenty of options that are under $100 that satisfy those criteria, so let's say around $100 at the top end.