wrote:
Also keep in mind that there is no REQUIREMENT to change to english
units. If you're going to fly your PIK exclusively, or nearly so, you
WILL get used to the metric speeds/heights, and instruments aren't
cheap (unlike me).
Jim


I'd second that - in the UK I fly my Open Cirrus metric, and this
creates no problems at all. The only mental arithmetic is 300m = 1,000
ft (OK, 996 ft), which isn't too taxing. Airspeed is pretty foolproof,
as if you try to fly the circuit as if it were kt (e.g. at 50) you'll
have stalled before you get close to the ground.

I'd think mph/kt confusion could be potentially dangerous, but kph/kt is
a no-brainer.