I have been using this BlackMagic Wheel Cleaner for a good while now and I swear by it. Especially with these chrome mag wheels, it definitely makes it shine!
Take a look... Notice the top picture is before I sprayed and wiped down. It looks an off brown, almost copper look. That's just all the dirt and brake dust.
Now look at it after I took about 5 minutes of elbow grease and a good spray down with the water hose. It's crazy the difference to me!
This stuff will work on pretty much any wheel. I definitely recommend it!