I heard the comfort issue with SS plates from one of my LDS's trying to sell me a Transpac. He said if I wasn't wearing a thick wet suit that the SS BP would be uncomfortable. I bought the DSS plate, and since I'm a big guy, I bought the big plate. As uncomfortable as that thing looks just sitting there, I don't even feel it on my back. I can don and doff the whole rig with a nuetral AL 80, 6lb SS plate, 8lb weight plates, and 16lbs of extra weight on it without a problem. I can see where this might be a problem if you couldn't "chicken wing it" to get out of it, or if you have problems lifting it to put it on
Once it's up, it's like there's nothing there. It seems to hug my back and the weight is so close to me, I don't have to lean forward with it on. It just sits there like it's part of me.
I brought it in to where I work so my buddy could see it, he was very skeptical. He thought it looked like some SM torture device. After he put it on, you could see the shock in his eyes. Even with the straps adjusted way too big for him, he still felt no discomfort. He's looking into one now
I can't speak to the comfort of other BP's, but the DSS one is like there's nothing there. Even when I put it on to show it off with just a T-shirt. I really like the hog harness too. It's more comfortable than the BC jacket I was renting, and easier for me to doff and don. I actually couldn't get the BC jacket with a tank on by myself unless I was sitting. The BP/wing, I can sling right up on my shoulder, then put my other arm through and I'm in it. I love that thing!