Generally we keep all of our units in metric when we are working with it and that is where a lot of things are quoted. The majority of our business comes from people in regions that use metric. (It is way better)
We noticed some strange behavior stitching images together that were taken below 60m on flat areas (corn fields) and limited the slider there by default.
For users that wish to map below our 60m limit, the altitude adjustment slider can be held down for 5 seconds to expand the range down to 25m.