The barrels on my rough SxS were pretty worn so I thought I would get some Perma Blue to touch them up, as I couldn't justify the cost of a gunsmith re-blue considering how cheap the gun was. Some pictures below.
I forgot to take a before photo but managed to find one which wasn't too bad... I don't think the end result was too shabby, it does the job for the rough old work horse.
Before:
After: