I have been using my nerd since like January, and I have few complaints. I got the wrong color, that's my main issue with it lol

One thing that was a must to me was being able to mount on the stem, cause my handle bars are all for holding, and it mounts like a champ. Anytime I'm in a sketch area, I can just pop it off and throw it in my bag.

I think I payed $48 for mine off amazon, not too pricy at all. I just have the 9 function model, which doesn't have the backlight. Sorta miss that a bit, although I wear a headlamp so I can see it if I'm intentional.

And as far as battery life, like I said, since January and have had no issues yet