Everything I've gotten from 2tall has fit a bit differently, some are a bit roomier there and some are a bit more restricting. I have to order two different sizes of each top I get, because some will fit better in the smaller size and some fit better in the larger. Tall Slim Tees has a smaller selection, but their sizing has been much more consistent for me.

I've never had an issue with feeling restricted in the shoulder area like you're saying though, so I'm probably not the best person to judge that, unfortunately.