I'm surprised no one mentioned Apex's 1/2 price replacement policy...
Wheel Replacement Terms and Conditions

 

If you are looking for the lightest wheels, these are pretty much the lightest in the world. They are about 1/3 lighter than forged aluminum and 1-3 lbs lighter than carbon fiber (and resistant to the damage subject to carbon by small stones at higher speeds). Litespeed is the company; forged magnesium, models are
RS5RR, lightest, and RS5R (for a slightly heavier car being tracked). I have the RS5RR on my 2024 Z06, which I don’t track, and are deciding what I am going to do for my forthcoming ZR1, shortly to be produced. Subjectively the wheels are better looking than the stock ZR1’s; a common 5 Y pattern.

To give you some perspective. My wheels save about 63 Ibs total for four wheels, over the factory aluminum. The key is the saving is from rotating weight.
My lightest wheels, as stated above, equal a saving of about 470 Ibs of static (non-rotating weight), a saving of 1 to 1+ seconds on 0-60, never mind savings on braking distance and steering/handling pluses. Just so you don’t get misled, they do not change top speed. Price is a factor and is approx. the same as carbon fiber wheels. There are other magnesium wheel producers but their weights are a bit heavier. You need to evaluate each one and decide for yourself as comparisons are never easy on a somewhat complicated subject. Being an aerospace engineer I enjoy delving into the technical details.

If you need more, send me a private message,

 

Lighter is better in every way, but don't let it bother you if you don't have the absolute lightest that money can buy:

 

Also, if you are really concerned or focused on dropping rotating weight, you should also consider dropping the diameter. I bet a heavier 19" forged aluminum would likely still have less rotational inertia over 20"/21" magnesium set.

 

Interesting!

 

Same here. 18/19 setup.