I'm intrigued by the L&M Vega light, but, there is no way it can be anywhere near as bright at a good Halogen lamp. And really NO WAY it can be as bright as a HID.
However, HID is also probably overkill for most road riding or commuting situations, unless you happen to have a huge hill you plan on riding mach schnell down during said ride.
I'll throw out a somewhat dissenting opinion here. Since this is a Tri board, and most of us therefore ride bikes w/ aero bars, computers, etc etc etc on the bars, you can easily run out of real estate on the bars for a light of any sort. (I had to jury-rig a mount for my L&M HID lamp onto one of the aerobars, since it just wouldn't fit anyplace else, and still be able to shine unblocked ahead of me. I really should just spend the $25 and get the helmet mount for it. The new ones come w/ helmet mount, mine didn't)
So - I'm suggesting you consider a helmet mounted, 10W-13W Halogen light. Something like the L&M Cabeza Logic or MV Solo Logic would be very good. JET lights single Phantom gets a perfect 5.0 rating in MTBR.com, so definitely look at that one too. (and for a few more sheckels, their adjustable Phantom i looks very nice too) Here's the link for reviews:
http://www.mtbr.com/reviews/lights/ One thing that I have found about having a helmet mounted light (besides freeing up dashboard space, that you may not even have had in the first place), is that, obviously, you always have the light shining where you are looking. This may seem obvious, but it is a BIG benefit. The most glaring (pun intended) use for this when road riding/commuting is to be able to shine your light directly AT drivers who are just about to pull out in front of you. Ya just can't do that w/ a handlebar mount. This has saved my bacon on numerous occasions.
If you do opt for a handlebar light, you might wanna pop for another $20-40 for an LED headlamp to supplement it. (PrincetonTec makes good ones, so does BD and Petzl) Allows you to read your dashboard, and is also helpful for looking around and if/when you hafta stop to fix a flat, etc.
edited to add: OK, so I just re-read the original post. The lights I'm recommending are all approx $200. That said, you'll probably want to spend at least $100-150 for a decent light. Anything less will probably come w/ a heavy SLA battery, won't have a smart charger (meaning, you can ruin your battery by overcharging it, vs. "set it and forget it" charging), and are likely more "to be seen" lights than "see where you are going" lights. If you really are going to ride in the dark regularly, you'll want a good light. Not a place to scrimp if you ask me....
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