I have the regular Iron X spray and the Iron X Snow Soap.
Regular Iron X works well for removing heavier iron deposits but it gets expensive if you want to use it regularly. You use up half a bottle (250mL) on one car, use it twice and you're out. Iron X is not a replacement for claying so some embedded stuff you still need to clay out.
The Snow Soap is nice in that you can wash the car with it. You use very little per wash. It pretty much saves you a step because you don't need to wash then iron x and then wash again. But it is not as strong as regular Iron X and it will strip wax off the car so you will need to re-apply that.
Do not use Iron X on bare metal - bare aluminum, iron, steel etc. It will eat and pit the surface!