So after much deliberating, I bought a Seasucker from that US of A.
Rather than buy one of their complete racks, I opted for 3 suction cups with ladder straps. Means I can put on one the saddle nose and then one on each of the grips.
Works like a dream. I've put the expensive super bike on it (I do own an Audi) and given it a bit of a pasting and it's not budged. When the cups do loose pressure (which they have never done when i've been using it) the pumps white shaft become exposed. So far so good.