I bought a Browning BPS about 30 years ago for Duck and Goose hunting. First time I went to the Salt Grass Marsh, the gun was covered in Rust.
I took it to a friend at Carter's country. He suggested parkerizing. It has held up well. Never had a rusting issue since.
I believe some of the newer coatings might have advantages, but the parkerized finish is tried and true.
