nick sorry you are wrong. .the 600 does not have a mandatory stabilisation system in fact it does not have one at all the ysas system that is in the 520 has just been certified now for the 600 but there is none available from mdhi. .. .also you wrote let the customer decide . .. .i did and i am happy with it the 600 is the sports car of helicopters [only upset that mdhi have not got any ysas yet..]. . . . <small>[ 15 March 2002, 09:00: Message edited by: md 600 driver ]</small>