From what I understand, harder metal, they beefed them up, so they are heavier, but they advertise the AF-1’s as the strongest cast truck on the market.
They say same turning as the Classics, but it didn’t seem the same to me, personally. I feel like they measure different for wheelbase when measured from axle to axle. At least they did for me.
And then the obvious, which is the new sizing.
And if you’re wondering, the only negative I’ve found with the AF-1’s, is the clicking they make.