I've had bantams. They can be fun but the eggs are really small.
This might depend on the breed. Pebbles was a batam australorp. She laid a really good sized egg. Lottie, Wyandotte bantam, lays a tiny one when she lays. They're the only 2 I've had any experience with but Pebbles wasn't much smaller than a Campine's on a good day roughly the same size.