Pros : Much faster and easier than going out to the grinder. Just keep a bucket of water handy to dip the pad.
Cons :
Other Thoughts : Mine has had two years of heavy use, and the diamond-coated sheeting is finally breaking up and coming away from the pad. It would probably have lasted even longer if I were more careful when grinding corners.
Pros : I do mosaics,and I use my sanding block after grouting,to smooth any little sharp places. It is quick,effective,and extremely easy to use. I really don't ever want to do without it!
Cons : The only con is that I don't have all the grits!