Does anyone have experience with using them? As in silver polishing cloths?(like this)
It says they're fine for most metals... but will the chemicals have any adverse effects on my (silver-plated) flute? Or should I stay on the safe side and not try it? I don't want to end up accidently ruining my instrument for the sake of a little shine!
Get yourself a microfiber cloth. They do a fantastic job removing fingerprints without damaging your flute. Some of the techs around here can probably give you a more detailed answer on exactly why you should steer away from treated polishing cloths, but the short answer is that they can leave minute scratches in the surface and clog the mechanism.
I also suggest you get a microfiber cloth. I keep one with each of my instruments, and they do a great job of keeping them looking great without stripping any metal, or risking getting chemicals in the mech or on the pads.
I just use the kind you get from the optometrist. For smaller areas, a q-tip and a bit of warm water helps a lot. For really dirty areas I put a drop or two of dish soap in an entire cup of water - just enough to work.
Though, to be honest, the only parts that need real cleaning are the insides. Most cleaning rods and such don't do half the job they should, so every so often I use a very soft child's
toothbrush and gently clean the inside. The last time I did this with my headjoint, it improved the sound greatly.