My favorite chain won't be YOUR favorite chain, because our priorities are different. I HATE the look and feel of a rusty chain. But, here in Houston, a rusty chain is easy to acquire. When the wind blows from the east, it brings in waves of toxic chemicals from the oil and chemical companies that pay off our local, state, and national politicians for the "right" to poison and kill the people of East Texas. When the wind comes from the South, it brings salt air of the Gulf of Mexico. Chains can look ugly fast.
So, my favorite chain is the KMC "Rustbuster". I am using the 1/2" by 1/8" version on my beach cruisers. It is model Z410RB, with a gray color and 8.6mm pin length. Month after month, this chain looks and feels new. Ideal for anyone riding near salt water, or living in industrialized cities where the pollution levels are out of control.