My vertical card compass is terrible, it sticks alot, then spins out.
And it is mounted up on top of my glare hood obstructing vision.

I frankly don't see the need for a compass much in a glider. I keep
orientated using landmarks like mountains (ridges are great),
rivers,lakes highways etc.

The gps is also good for direction in straight flight, but I just use
a digital display, not a compass card display.

Todd Smith
3S