Never-dull will scratch aluminum. you may not see it but through time you will. I have a complete polishing set up, hand held (for large stuff like wheels) with 6-8-10 inch wheels and a bench polisher. I have several types of wheels and many flavors of compounds. Never-dull is good on rusted chrome or hard to remove debris-built up. I also have a wheel jig I use for wheels for a chrome like finish. It's power driven, takes a lot of the work out and does things really fast.
There is a lot of good polishes available now, I stick to mothers because it works and will not scratch. For just normal cleaning I use the mothers in the red plastic container. Does it good and doesn't take long. For a real high shine I use mothers billet.
If you want in a good detailed for wheels consider a 10 inch buffing wheel with red rouge.
With the center stand it makes it really easy to do.
Just a thought
dirtdobber, I have used never-dull for over 40yrs. It is made for aluminum. Still have some of the aluminum I use it on that is now 30yrs old and have never seen it scratched. You sure your polishing cloth did not have dirt in it?