I don't see anything about operating position.
Higher powered CFL's are available in retail outlets in the US than you find in retail outlets here. However, anything above about 25-30W comes with a warning that they must be operated base-down through to horizontal, but never base-up, as the heat from the tube will overheat the electronic control gear in the base.
This is just speculation on my part, but one reason you might not see those here is that the British and EU standards on measuring lamp life of GLS lamps requires when to be operated base up. If the same applies to retrofit CFL's (I don't know if it does), then these high power ones are only going to get a rather short operating life before electronic ballast is cooked by the heat from the tube.