I have a small Balance, which is what the weight/height chart recommends for me, but I also have the issue with struggling. When I bought it, it did not seem like a big deal, even with a wet suit. But later I got a wrist computer and camera, then once I added a flash light, on a rocking boat, in the dark...
What I'm saying, is if you can make the next larger size fit to your minimum size (no wet suit), then get the larger.
I really believe the problem is that hte shoulder straps are just not long enough to get the maximal length to fit without undoing the shulder buckles, which are a little difficult to fasten once you have the suit on, since it is not readily in view, and since they articulate, it is difficult to fasten them by feel.
I haven't tried to don/doff underwater yet, but I think I might be in for a challenge.
All that said, I feel it is comfortable and supportive. It actually is more comfortable with a tank on, than unladen.
Good luck