Yes, put the battery you get good results with in the mutant and see. Also - If contacts are oxidized, alcohol and cotton is a waste of time. Fine sand and re-clean contacts.
Don't forget the 510 threading and all body connections.
Sanding contacts will remove the gold plating and lessen conductivity (but will still be better than some solutions). A standard pencil eraser would do a much less aggressive job, but it's not a guarantee you will not remove some of the plating or all types of corrosion. Alcohol can still remove light corrosion in a lot of cases.
I don't know what the view is on using such products in the case of vaping because of possible toxicity issues, but the best contact cleaner you can find (as far as I know) is DeoxIT (pro gold for light corrosion and red for heavier corrosion); it also protects and lubricates contacts. You only need a drop on a q-tip and make sure you don't overdo it and let it fall in the gap between the contact and threads as it is conductive and I have no idea about the toxicity of it, but if done properly there should barely be any left on the contact. Worst case scenario (actually should be done after using a contact cleaner on a PV no matter what IMO): rinse it out with a couple of drops of alcohol and wipe dry a couple of times (make sure the unit is off during the whole process for good measure). I also found some fine tip q-tips at the electronic store that seem to get pretty much to the bottom of the gap, but they're very fine and don't absorb a lot. There should be some contact cleaners approved for the food industry that might be less risky to use but I don't really have the time to research those at the moment.
