Does it really work? Does it not reduce image quality in the process? How "essential" is it and which one should I get? I have been looking at Noise Ninja, and despite it being available as a free download: The grid pattern does not sound very desirable. If I was to purchase a liscence, which one? There are so many versions to choose from. http://www.picturecode.com/purchase.php Any advice would be greatly apprechiated.