...Once again it is important to understand that construction quality is not put to the test the same way on a 6m flying 30+ knots or on a 12m flying say 15 knots. You will probably not have trailing edge problem on bigger kites (I don't have any on my 9 rev). ...
Interesting theory. Can't say I can comment, I own a 7, 10, and 14 kite. I fly the 14 most often, than the 10 and then whatever small kite I own. For that reason I tend to keep the small kites longer because they get a lot less flying time.
I haven't seen trailing edge wear on any of my SS kites, but perhaps if I lived in an area with ballistic 30+ wind as the norm, it would be different. The original poster, though, is looking at an 8M. He's 120 lbs. He's not going to be flying it in 30+ winds routinely so I think yes, despite whatever theories you have going around, he is going to rock that 8M, love it, and not see this issue!
So this tangent is pointless. mdiggs, get the 8M you asked about!