In reply to Jamie Bankhead:
Take a look at the Silva Jet S1
The Jet series compasses have a wider needle that's far more stable than a standard Silva needle.
This compass is actually an Orienteering compass, so it's easy to use (at speed). The only down side is it's not cheap. I have one and its now become my hill compass as well. Expensive but very good item of kit.
I also have a Moscow thumb compass, which is ok, but if the quality of it is anything to go by, I don't think I'd be keen to rely on one of their other compasses as a hill compass to last years of use.