Well since it is bumped into 2013...
The largest soft one I ever saw was a married buddy who would meet with me to "play" occasionally. The first time we met to get naked, I was unaware of his size. I noticed a bulge, but nothing special. When he took his pants off, his briefs (tighty whiteys) were also "average". But he was tucking it under his balls toward the back! When the briefs came off, he had what I guessed to be about 9 to 10", but kind of thin. He had this really kinky curly hair for pubes that made it look even bigger. He got good and hard and it did not get much larger hard. He loved being sucked, and he had huge loads, too. He was not really into anal, so we concentrated on touch and oral. He was a normal, nice guy looking for a little something fun and safe. He had never been with another man, and when I asked what others said about his huge cock, he said his wife was the only other one to get to play with it, and she liked it "alright, I guess". Nice memories of a gentle giant.