Quote Originally Posted by Archerfish View Post
Technically speaking, both are alloys. Basic steel alloys are a combination of mostly iron and carbon. Chromium is added to make the steel rust resistant.

Whenever we say alloy wheels, we usually refer to cast aluminum wheels. These are lighter but more expensive.

Some very high-end wheels are made from magnesium. So the expression "mag wheels" or "mags" originally described magnesium wheels. However, it became a marketing​ term.

Ordinary shops will often refer to "rims" to describe cheap looking wheels​ and "mags" to a good looking one.

Generally speaking, a more costly wheels means its tensile strength is better and of course lighter. Most experts will recommend that you stay away from cheap, unknown brands.

Take note that some dealers or insurance companies will not honor any accident related claims if you replace your wheels, should it fail and cause an accident.

References​:

Design of Machine Elements
by Virgil Moring Faires

High-Performance Car Mods
by Matt Cramer
I really appreciate it that you referred expert opinions. Choosing the right wheel is very confusing. There is always the looks vs the cost. There are so many wheel shops & most of these look really nice & the price is so tempting. Unfortunately, most of them are low quality fakes made in China. Some are so well finished to pass off as original. I have friends who used to drag race & rally, & they said that spin offs are dangerous, since there have been instances of them fracturing. They said that if you want the durable ones & just to be sure those are not fakes, buy surplus wheels (OEM) or ROTA’s.