Whatever you do, be sure to spend the extra $10 bucks or whatever it is, and get them from Geoman and not Dealexteme (I buy plenty of cheaper lights and things from DX, but I wouldn't buy something of this price range from them).
If there were ever an issue, you'll have a much easier time of getting it handled as apposed to DX, plus Geoman ships much faster.
A couple quick notes that may be helpful:
A lot of guys that want to mount it on their helmets automatically buy the helmet mount, but for a lot of helmets it's not needed. So look at your helmet and see if you have a vent down the center. If so, you can mount it to one of the cross bars on that center vent just using the rubber O-ring you would use on your handlebars.
Lastly, when you're using it, and you want to turn it off, just hold the button in for about 2 seconds and it will shut off. In other words you don't have to cycle through all the modes to get to "off".
I bring this up because on last nights night ride, several people had new magicshines and I noticed everyone cycling through all the modes to shut it off when we stopped to rest.
When I told them they didn't have to do that, they were all like "ooohhhh, that's awesome, I didn't know that!".
Oh and sorry to have aided in this thread hi-jack😱