I am prejudiced, but IMHO the Ithaca M37 is the best pump shotgun ever made.
You're not by yourself in that position.
It is a great one, light, handy and tough.
I toyed with getting a M-12 or a M-37 back in the day as a lad, picking up pecans, saving for my first shotgun.
My great uncle was a trap shooter, ended up with an attic full of silver bowls and trophies. He owned a hdw. store plus a bunch of other businesses, was well respected by me.
I presented him with my delema. He drove a big Buick Roadmaster. His opinion, the Ithaca was like a Ford, the M-12, a Buick. So, I got the M-12.
Today, I have 2 Ithaca 37's, no M-12. 37's are lighter and handier, although the M-12 is a tough shotgun. I eventually traded the Winchester.
DF