Fred,
I flew my electric model, the same one I had at the recent fly in on mt leinster, and had no hasstle there at all. That was just under 3m. It is a slope that you need to be good on the brakes as you need to pick your landing spot carefully. Glass models with foam core wings etc up to 3m with airbrakes would be great. The thorny scrub really would not do much damage to these.
cheers
D.