I used a wired Cateye Astrale 8. This may be discontinued. I bought one recently from Nashbar or Performance for $30. I generally am more interested in my cadence than my current speed and this model allows the primary display to be the cadence. The current one as I remember only shows speed as the primary display, but I may be mistaken. Cadence, Average speed and Max speed are what I like to see and this unit gives them all.

My first one lasted a long time. I ride near the coast a fair amount and the electric contacts needed cleaning fairly often and I may have scrubbed them to the point that contact wasn't good. Never the less I got probably 10 years use out of it. Liked it enough to replace it with the version that replaced my original. I didn't want to pay for the wireless version and there may have been the display issue.