I own both.
M37 is lighter
BPS is stronger and has tubes.
I use to use my 16 ga M37 for upland, until I got my double. I still pull it out once a year and kill a couple birds with it for my dad, he left it to me.
My 3 1/2" BPS is my go to waterfowl gun. STONE reliable and doesn't throw hulls all over the wetlands.
Both are smooth good guns that dont feel flimsy or cheap like a 870.

Music washes away the dust of everyday life
Some people wait a lifetime to meet their favorite hunting and shooting buddy. Mine calls me dad
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