With a medium speed film like FP-4 or Fuji Acros souped in a high acutance developer like FX-39, I can coax 16x20s from my Leica that fool most people into believing that they are from medium format. I rarely print bigger than 8x13, though, and at that size the portability and ease of use of 35mm will trump medium format every time, with very little if any difference in print quality.