i'd recommend a cateye strada micro wireless and it's from a top brand in bike computers. never had reliability issues over 6 years of using one. very customizable settings as well. only reason i bought a 2nd was for the color - to switch from white to black.

batteries last forever. only reason i chose wireless is for aesthetics - just as reliable to me but it keeps the lines looking cleaner on the bike with one less wire running somewhere.. i wish my bike had internal cabling that's how much i dislike wires running about the frame.