Succinctly, expect massive shrinkage. I'm 5'11" and 175#, so I'm a clear "medium" size-wise. I traditionally have trouble with LLBean body lengths however, so I actually called and checked the body length on these shirts before ordering. To my delight they were quoted 5" longer than the competitive mock turtles I've been wearing. I ordered 3. After the first washing - in cold water - all three had lost 3 1/2" in length, making them nearly the same as the too small competition. Still debating whether to return these or - ironically - to order more, because they are still 1 1/2" longer than the alternative!
Different sized people will have different reviews, I am wider in shoulder and chest than many and find it extremely hard to find a proper fit. These Mock's fit me perfectly. The quality leaves nothing to be desired. I have dealt with L L Bean for years and have found no other retailer to be in the same hemisphere. The only thing that could make me happier would be "Made In America" on all L L Bean products and yes I would pay more without any hesitation.
I bought two of these last year despite the many not so positive comments. My own experience has been very positive; this is an excellent product for a great price and I have been wearing them all the time. They pretty much look like new and I just purchased a few more.
I just placed my second order for 2 more of the mock-turtleneck shirts, after receiving my first 2. The quality, fit and comfort were just so great I had to have more. Thanks for a great product as always.