6x6 backs are available for the GS-1 but if you primarily want to shoot 6x6 then the Bronica SQ may be a better choice as it is smaller and lighter. The GS-1 in 6x7 should be an excellent landscape camera as it is one of the most portable of the interchangeable-lens 6x7 options (except of course the Mamiya 6/7 rangefinder). The one disadvantage of the GS-1 that you should be aware of is that the wide (50mm) lens takes a 95mm filter, which is different from the filter size of most of the other lenses (72mm). This makes assembling a set of filters a bit more expensive than if all the lenses had the same filter size.