The Lumos' big downside is that they're unadjustable, so depending on the angle of your bars, there's a good likelihood they'll be improperly positioned for best viewing angle. They're definitely insufficiently bright and have a very poor beam pattern, so to light a pathway is way beyond the capability of the Lumos.

That said, I do like mine and they work well on on one of the bikes, which positions them at just the right angle to shine inside a sedan's cabin from about 4' back. Otherwise though, they're useless, really, except as marker lights; brightness is decent with a fresh set of lithium AAs.

Here's a pick of the Lumos and the Road 2 on my minivelo: