If you have the dough, you might consider the new Zeiss finder. If I remember correctly it does 21/25/28. It does not change magnification -- it does framelines. It is incredibly clear, and I don't really remember much distortion. The bad news is that it is 400 something bucks. (I think it is Zeiss's secret plan to make up the difference in price between their bodies and Leicas with finders and hoods).