China Spring switched to military immediately in the late 80's and had quick success. They still had corps uniforms and equipment, too. Now, you are somewhat correct in saying it takes time, but there are exceptions. Incidentally, I have seen and judged many a military band that used tonal bass drums. Scotch drums are available but not always easy to get in a timely manner. Bottom line, the initial cost of getting everything in place will still pale compared to today's "marching arts" bands. Military bands won't be spending thousands upon thousands on props, music and drill every single year.