I decided to remove my B-Square Mount on my mossberg 535 shotgun. I ordered a Picatinny rail to replace it.
The B-square mount was not secure and would rise on the recoil of my shotgun. I'm not sure I had it installed correctly but the picatinny rail is a cheap (7.00) fix. Taking it to a gunsmith would be much more.
I plan on using the 535 with it's slug barrel for whitetail this fall in Allegheny county, which is shotgun only.