I've used brite shine, & autosol before, & have heard good things about purple polish too. I will give it a go too one day.
Mirror finish is the best available IMO plus Aussie mad and owned " align="absMiddle" src="/DesktopModules/NTForums/themes/_default/emoticons/smile.gif" /> Lots of detailers use it I reckon its the best out of all I have tried and i switched from purple to this stuff http://www.mirrorfinish.com.au/metal-polish-trucks-cars-boats-motor-bikes-household-and-industrial-applications
Never Dull very little effort even on old bling
No need to try any other products, Purple Polish is great for polishing aluminium and its fine for Chrome. Im not into Harley products but they do sell a great Chrome Polish and its smells like vanilla when your using it, it does work well