This picture is of an incline Kay encountered in Washington, DC. She has 'Leo the L'ion' (the large lithium ion battery) and she says she had "no stalls and no problems."
Kay is 5'9" and between me and Rhonda in size. I don't think I could climb these inclines, even with Leo, but I have better results with Leo than I do with the cub (the smaller lithium ion battery).
Kay also says that she has the larger seat and when she sits on it and uses the backrest that she has plenty of room for her legs.