Ease of fitment makes the wireless ones very popular. They work very well-until a problem comes in and then they can be a nightmare to sort out. Don't ask me why but they do.

The wired version look a bit untidy and can be prone to damage of the wires but in 20 years I have only broken one wire and luckily that was repairable.

So what do I use? Garmin GPS. No wires- no sensors and cadence can be fitted if wanted. I also have 3 heads and 2 sensors for a Cateye wireless in the spares box. That is due to the problems that came in after a while on getting them to work. And the Tandem still has a Cateye Astral on it as in 8 years it has given no problems- and only changed the battery once in that time.

And on cadence--You think you need it but I rarely use it now. I know my comfort cadence and if I want to pedal slower-I do. I only utilize it occasionally to see if I am in the right ball park- but can be interesting to find out how slow you pedaled up that steep hill and still kept upright.