The birds I tell you - watch for the bloody birds. One hit dead on the windscreen while doing an exhiliarating 300 knots plus at low level (below 10,000) and you will lose an eye at the very least and your whole head if its a BIG bird. It is simply not worth the thrill or the risk and the passengers won't go to your funeral - although their lawyers will. In any case you are saving very little time by keeping high speed below 10 when compared to 250 below 10. High speed below 10 is for thrill seekers and suckers.