In my extremely limited experience...
North UK - £30-£40/hr
South UK - a bit more, though I haven't heard of anyone getting £60/hr.
So better paid than f/w, but...
A lot less work around; just not that many schools.
Usually half hour trial lessons, as someone said.
Usually longer briefings - not sure if that's a difference in the schools, or just that there's more you need to know to fly a more complicated machine.
Pretty knackering due to being more dangerous, if teaching hovering you need 110% concentration and the fastest reactions in the world.
Maybe a bit like teaching landings, but with no circuits in between. After all, no-one has ever collided with the sky.
But I do think f/w instructors should be paid more too, actually.