I am currently looking at some aftermarket 18x8.5 XXR 006 series wheels for my 8. I am aware that the stock 18" wheels weigh roughly 21lbs each, and these XXR wheels weigh about 25lbs each.

Will I notice a difference in the way the car drives/in the performance of the vehicle due to the heavier wheels?

 

You might notice a bit...but on a street car it will be hardly noticeable

There are differences in tire weights as well...so if you choose wisely you can lessen some of the wheel weight difference

 

what he said

street, not really, track, really

 

It's currently my daily driver so I'm just hoping for no real huge change that makes the ride slower/more uncomfortable.

 

it might cost you a bit in gas as well....I know that when I went to big tires on my truck it cost me a few MPG