I always use my rings, couple of things, I feel that a normal lens is sharper, I am sure there are others who like the macro lens, you can get more magnification with the rings than the macro lens, unless you go with a specialty lens like the Minolta 3:1, I use the rings over the belows due to the fact they couple with the exposure system in my camera and I don't have to figure extention factors to get the correct exposure, I also have several reversing rings, and I still use the extension rings due to the meter coupling, most of my commercial work now a days are macro shots, and this works out well for me. It is often overlooked, that the regular lens is one of the sharpest lenses around, my 50mm f/1.7 is one of the best lenses I have.

Dave