Cateye again and I would say any of them. The astrale 8 with cadence is great for finding out you do not pedal fast enough- but the cadence feature can be tricky to set up. The wireless ones are fantastic till something goes out of alignment or "A" battery runs low. and the wired ones work great but do look messy with the cabling.
I have used all of them and swear at all of them aswell. I do mean it that way- They all have their faults in setting up. But whatever Make or type you get- Put the set up instructions away somewhere you WILL remember where they are in 12 months time. I can never find mine when I want to fit a different wheel size or change a battery cos it has gone flat and it resets itself to Zero.
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How long was I in the army? Five foot seven.
Spike Milligan