AgreedI'd go 37 psi.
Better fuel economy?50 is ridiculous. Pushing boundaries of tyre specs.
Why not go as per Merc recommendations? 32 is fine for normal 2 up use, same for 4 up. Only if you are really loaded as in camping gear or caravan towing, would I go above the 32. Any more just adds to the harshness of ride and doesn't give any advantages.
Ian.
Better fuel economy?
37 psi is only 2 psi on the front and 1 psi on the back more pressure than stated in my fuel flap. I have done numerous testing over periods of months going to a from work and seen gains of up to 6 mpg.Marginal and surely offset my uneven tyre wear and trips to chiropractor