Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

That might be useful if I could have it rotated so it's visible most of the time while I'm on aero bars.

Both my 310 and 910 display power, and the mounts work to keep them the correct way up when on the aero bars... you just need a Forerunner specific mount or Barfly which can cope with both Forerunner and Edge mounts .