Recording vocals with a 57 or 58. Tips?

I now own an SM7b but before I did I would take an sm57 or sm58 no ball and put a pop filter the exact same distance that is between the grill and capsule of the SM7b. It was a good reference for mic distance.

http://www.homestudiocorner.com/wp-content/uploads/2009/06/img_0137.jpg

To be honest when I "upgraded" to the SM7b the difference wasn't as drastic as you'd think.

I sometimes feel like it was only more money because of the body, hi pass filter, and presence boost. Which i generally leave flat anyway.

My 2 cents. \m/ \m/