I originally purchased the 4oz. containter with the basket and minitature scrub brush.  I literally just dropped my jewelery in with the intention of leaving it to soak for a couple hours.  However I forgot about it and only remembered what I had done more than a week later.  I was so scared that I had damaged my wedding rings that I was literally shaking when I removed the basket from the solution.  To my surprise the rings were sparkling clean, including my diamonds and it was in perfect condition.  I didn't even need to use the brush.  The long soak had apparently done its job and completely dissolved any gunk from between the crevices.  All it needed after that was a quick rinse with tap water and a clean cloth to dry. I was hooked after that.  This cleaner is obviously not harsh on your jewelery and it cleans beautifully.  I now rountinely just drop in my jewelery and forget it.  No matter how long it takes before I get back to it, they are always sparkling clean and in perfect condition.

The only reason I did not give it 5 stars is becuse I haven't tried it yet on costume jewelery.  If it's purporting to be able to clean costume jewelery then I suppose I can't give it 5 stars until I know it can do ALL that it claims.  But even if I realise it doesn't work on costume jewelery I would still continue to buy this cleaner simply because it is a no hassle worry free way to clean my real jewelery.  I am so impressed that I came back and ordered the 16oz. refill bottle.