The HeadBlade ATX works well around the ears since the blades trail behind the wheels and you can get in there. Not so with the Sport. And the learning curve for the ATX is faster than the Sport, but the Sport gives a closer/smoother shave than the ATX.
I have both. The ATX sits in the closet, and the Sport gets daily use.
Unfortunately Walgreen’s and the rest only give one slot on the shelf to the Head Blade people and thus they can only sell ONE of the two options and for now, that is the ATX.
You can still get the Sport online, and Head Blade says they plan to support the Sport via web sales.
Mr Zed