Hi, FinkFloyd. Have a stroll though this thread. Questions you haven't even thought of are covered there.
https://www.bikeforums.net/track-cyc...computers.html
Feel free to ask questions there. Everything there is still relevant. Track PMs don't change much over the years.
Wireless power meters require maybe 3s to start recording data. Wired, with two reed switches, can start after 1/2 a pedal stroke.
This is because Torque data travels with the Cadence data into the head unit which calculates Power. So, when you have cadence, you have power. No cadence, no power. That being said, only standing start specialists (Tam Sprint, 500M, Kilo, etc...) would want wired. Wireless SRM would probably suit your needs.