Grinding Welds?

I use this for quick heavy grinding this is about 3x's as thick as a regular cut off wheel
http://www.bestbuyautoequipment.com/3M-Automotive-Products-3M-1991-p/3m 1991-01.htm

and then finish with this

http://www.google.com/products/cata...a=X&ei=6fqST7rnLdKdgQfkhYGPBQ&ved=0CHQQ8wIwBg

If ur gonna grind it grind it, no sense in rubbing it to death.