The largest top that I've made with the S8 tip is 4". It works fine, but I don't think I'll try anything bigger. While the small tip functions well, it looks odd; almost aesthetically unpleasing. Also, the S8 tip limits the diameter of string that you can use and I like a thicker string (rope) with bigger tops.....
With that said, when considering the question at hand, "who would buy a strummol 8 derlin top if it was a 3-4 inch and still used a s8 tip", I would buy almost anything that Maurizio decided to make.......and I would buy more than one.......