All joking aside; you can actually hear the difference between a stock 400 and a stock 428. 400 has a 3.75 and a 428 has a 4.00 stroke. When they went to the 4.21 stroke in the 455, not as much improvement was made. I think 4.0 is the 'sweet spot'.
Also is the fact that it's a little more 'exotic' to have a 428....
-I actually believe it was the only engine that was painted orange, in pontiacs...-not that it matters..
