Ripp - it can badly affect some types of stock finishes and it is fatal to any kind of plastic. Just make sure you keep it in the bore where its meant to be... I use it but prefer Montana X-treme copper cream (they also do copper removal chemicals) but that's partly because I have always used that type of cleaner since target shooting days and because i found out the hard way about the negative effects of wipe-out foam! It also eliminates the need for brushing and keeps on top of carbon rings etc.

As regards powder residue, wipe-out is a copper killer. They also make carb-out specifically for carbon, although I am perfectly happy with carburettor/engine cleaners for this, particularly Mercury / Quicksilver power tune which you can buy over the net or any Mercury Marine dealer. It works and is specifically designed to remove burned carbon and other deposits without damaging metal.

There is actually a 2 page review of wipe-out in the current Precision Shooter mag but I haven't read it yet...