It depends on the design of the back and how the harp fits against your body. My Crescendo has what DS described as “hybrid stave back”, so not really a full stave back but enough to make a difference. I like it and it is comfortable on it. My Cheyenne has a square back, but MusicMakers pays a lot of attention to their harp design to ensure comfort so the harp fits against my body really comfortably despite being quite a bit bigger overall comrade to my Crescendo and has a square back. My pedal harp has a round back and it is not very comfortable against me because I am a small person and the back of my pedal harp is quite bulky for someone my size. I tried a pedal harp from another company and the way that they taper the soundbox makes the harp a lot more comfortable against me. If I have to choose a lever harp sight unseen, my inclination is to choose something that is not square back if the sound box looks quite boxy over all. My harp friends also prefer staved over square, but like I said my Cheyenne has a square back and the fit is very comfortable so I don’t want to say square back is always a no no.