I have the Dinotte 200L with AA batts and it kicks *****, very excelent light. I used it for a brevet series and it gave 4+ hours of light on the low setting (which is plenty bright for 25 MPH, IMO) in 50 degree F weather. I use 2600 mAh rechargeable batteries from battery space.com. Perfect beam pattern and no dimming ever. A nice feature is the flash mode.

I also have a Fenix (fenixstore.com) LED flashlight with a 3W Cree LED. It runs on 2 AA batts. It's high beam lasts for around 4 hours and it costs $56.
I would get 2 of these and use them on med pointed close, and high just in front of the med beam. The only problem here is that you will need to fashion brackets. Pipe clamps and some tape would be ugly but effective.
It also has an "ultra" beam setting that lasts for less time but claims 135 lumens, and it is really very bright.
It also has a seizure-inducing flash mode.

I will buy LED lights over halogen every time, now.

Oh, I had a Sigma Sport and Light and Motion halogen lights previously and liked them both, but the LEDs are way lighter, last longer and are equally bright.

One last thing to think about: Light placement. Placing the light on a fork blade will make better use of your lights, ilumination road anomalies more clearly.