I own a gold plated trumpet, over the three years I've owned it I kept it clean but never polished it or treated it in any special way. Many brown spots were showing all over my trumpet and it looked slightly discolored on other parts, so I decided to give this cloth a try. I initially washed my trumpet and dried it with a different cloth, then over a week I polished it 3 times for 15 minutes each, with this gold cloth. The initial polish really didn't show a difference. Now after the third time polishing almost all of the spots have disappeared and the lovely (and slightly rose) golden color shines bright again. I think a 4th polish in a few days will finish the job perfectly. (I assume you could also sit down and polish for an hour straight, certainly not my preference)
On the costs: I used a quarter of the cloth to restore my trumpet, that part is pretty much black now. Can't comment on the usage of the cloth based on regular maintenance, a friend told me he replaces his silver cloth every 1-2 years.
