Only had my LT2/RS automatic for a couple months. But I did drive it a few hundred miles through one of the worst rain storms I can remember at speeds greater than 70mph. It handled great. A lot better than my 06 Si 4cyl 6sp manual.
I drove my my Si through 7 Cleveland winters with 17" low profile performance tires without a spot of rust and no accidents. 54 mile commute mostly highway into downtown Cleveland. I did believe I was going to die at least twice a year.
Anyways the Camaro has a higher ground clearance, 20" tires(thicker wheel walls) and a lot more weigth. I can't imagine the rear wheel drive will make it worse than what I'm used. And like that other guy said regular washing in the winter reduces the chance of rust.
If I'm wrong I'll let you know in a couple months.