azrocketman

I'd say it really does not matter for typical use which wheel you use. Alloys can be lighter than steel assuming that a lightweight alloy is used. Some mag wheels, like the old Cragars, are steel. The racing wheels that offered the greatest weight benefits were magnesium (like the old mini-lites). Magnesium is not a material of choice for everyday use in wheels since it is very susceptible to corrosion. The biggest advantage for street use of an alloy wheel is the variety of different styles available.

Much was made of the light weight and energy storage in your reply. Energy storage works both ways. It can be a disadvantage when trying to accelerate and brake. It can be an advantage in that it acts to smooth out the power train by acting like additional flywheels. In typical use it really does not matter. If energy storage is your prime concern (which I doubt) consider using the smallest (diameter and width) wheel and tire combination that you can (like the front wheels on a drag car).

Unsprung weight affects the handling of a vehicle. You would like to minimize the weight of the tire and wheel combination (plus some of you suspension components if you're serious) for better handling. Of course, for better handling you'd also like to put more rubber (means more weight) on the road. Let's face it, these are trucks with solid rear suspensions and mediocre weight distribution. They can be improved but they will never be competing against sports cars (maybe against sport utilities). Again, for typical use the alloy versus steel comparison really does not matter (steel wheels may have an advantage for competition in that they can be sliced and diced to make custom widths and offsets for serious competitors).

My summary: Do what looks good to you and is good to your wallet.