Reliable Bike Computer
I use a Cateye Strada Wireless on my mountain bike. It's taken quite a bit of abuse and hasn't let me down yet. My only complaint is that it's easy to reset your trip info by accidentally leaning on the computer for a few seconds. This can be seen as a benefit as well, as it's easy to reset your distance if you're navigating and need to know how far until your next turn even if you're wearing winter gloves. It's a basic computer, no cadence, GPS, HRM, or anything like that. That stuff just takes the fun out of riding anyway.

I'd recommend that you loctite the wheel magnet, they'll come loose over rough terrain.



They get good reviews at Amazon too.