I have ridden the bike with the alkaline and NiMh D cells in freezing temps (the coldest was only 30 degrees F, so not real cold), and the bats continued to work just fine. Alkaline can get expensive but you can usually pick up a 12 pack of D's from Wallyworld or SMart for about $8 to $10. You have to remember that when using one beam (which is all I normally use) the batteries will last for 5 hours of continual use...I never ride for 5 hours at night; the most I used the light at night was for 2 hours. Two sets of alkaline batteries lasted me 1 dark season. I already had a recharger because my kids all have stuff that use batteries so I bought rechargeable batteries and a recharger for their stuff anyway, so the rechargeable battery for my light was a no brainer.

With a system like mine I have an option, I can rechargeables or not. If my rechargeables (by some odd chance) go dead on a ride I can buy regular bats at any store. If I had a light that only had a rechargeable system and the bat died I would be riding without a light the rest of the way home. So I'm not a slave to the wall outlet like most other lighting systems.

If you have the money to spend more on a lighting system and want to use regular batteries but also want more battery life there is a system that Performance sells made by NiteHawk called the ViewPoint Gen3 that runs off of only 4AA bats with 10 watts of power and will last about 5 hours on high but it cost $139 for the longer lasting version.

And the lights that I have encountered on the road that other cyclist have used ARE NOT very visible, if at all, from more then 20 to 25 degrees off angle. I'm talking about being in a car and approaching someone on a bike with a light. Anybody that has used a flasher was more visible from at least 45 degrees off angle, and my flasher is visible from about 90 degrees.