I didn't think to get a before picture but here is the after...

Nice shiny bathtub! The pin says to use the blue Dawn soap but I used my off brand clear dish soap and it worked just fine. I still had to put a little bit of elbow grease into it but I think that may have been because I ran out when I got to the 2nd bathtub so I didn't get enough coverage. I'll try a cup of each instead of 1/2 next time.
A definite Pass for this pin.