Thanks!
It's very hit and miss, which I think adds to the experience. You never really know what will turn up and when a front liner turns up it really makes your day.
I've been there on hot sunny days and only seen one helicopter and I've been in the middle of winter with thick fog that I would have thought would be impossible to fly in and had front line fast jets come through.
Been meaning to go for at least two months now but it's a long drive for me (isn't cheap with fuel prices either!) and I want to pick a day with good weather. So far the weather isn't playing ball.