I use either Britemax iron max which is much much better than Ironx in my opinion as it also has cleaning ability, doesn't smell bad at all and has a double agitate so spray on then once you think it's broken down agitate and it will start to attack any remaining dirt and Iron. The other one I use is Sonax full effect wheel cleaner, normal wheel cleaner with built in iron remover.
Being honest though if your not looking after the wheels regularly something like bilberry is good enough.