My M model has 457 lb useful load. I have removed the wheel pants and brackets, hardware, etc, and pulled out the useless LORAN unit that was still in the panel for some unknown reason when I bought it just a year ago. I have not been officially ready-weighed, but useful load has increased by a modest 15 pounds (my estimate- calculations by a properly licensed professional actually indicate a couple more pounds in my favor) giving me 337# of humans and stuff to fly around with and still have full fuel at takeoff.
* I have flown Pete’s airplane. It’s a great airplane, (I can see it from my house, it’s tied down next to mine,) and it is solid, well taken care of, runs and flies spectacularly, and I would have bought it if he was selling it a year ago when I bought my M.