I am 5'4", about 300 pounds, and wear a women's size 24-26. I carry most of my weight in my middle. I rode EE at the passholder preview in January and again this past weekend. When I rode the first time, I could not get the lap bar to go down and a very nice castmember asked me to stand up, helped me push the lap bar down and then asked if I was okay with it (as it was pushing into my stomach somewhat). It was somewhat uncomfortable, but I really wanted to ride, so I said it was okay. He said that the lap bar has to go down to the first "click" before it will latch.
This past weekend, I rode it again and had to remain standing, push the lap bar down until it clicked, and then slide my stomach under it. I had read on the boards that there were some rumored changes made to the lap bars so that they did not have to go down so far to click, but I could tell no difference in the bar from the ride I had in January. I rode twice this past weekend, and though the lap bar is uncomfortable for me, it is not uncomfortable enough to keep me from riding - it just presses in tightly on my stomach when I ride.
Hope this helps!
Susan