Bike computers are great, but I've only had one problem with them. (For Me) it seems as though the wire/cable between the cable and sensor is the weakest link in the durabilty of a computer. I recently solved this problem by getting a Wireless Cateye comptuer and am Loving it. A wireless computer may cost you twice as much, but I would expect it to last atleast twice as long. If your only going to see if a computer is "right for you" then getting a less expensive =<$20 cateye is still worth it.

Good Luck