900 lumens is a lot to have just riding at night with. I have a Cygolite MityCross 480 and I rarely ride with it on high.

I had a MagicShine, it lasted 2 months, I sent it back to Geoman and never heard anything more about and that was after 4 or 5 dozen e-mails, now 14 or 15 months later nothing. They only have a 3 month warranty because they know how cheap it was. And that was my mistake for buying such a thing, but I ignorantly thought that since all LED's come out of China anyway that maybe they can make them that cheap and last...nope. And that Magicshine was no brighter then a Cygolite ExpiliOn 350 I also bought and the ExpiliOn lasts longer in battery usage, as does the the MityCross.