@accab
I just purchased a S kit from Fulham. I wear S for Nike/Adidas as well. Its definitely not body-hugging as you may see from the players on the field. I got the third kit anyway, the collar area is a little loose. If you were to get a 2 sizes up, expect a very loose looking collar. If you prefer a looser cut, just take M. L would make it too long in terms of length.
Of course the sizing chart provided has its merits, but this kit isn't Kappa Kombat which is certainly more tight-fitting.
Here is a picture to better illustrate. I have used a 08/09 Inter Milan kit which is also S size.

As you can see, width wise, the inter kit is slightly looser than the kappa kit. Length wise, its almost the same.
It really depends if you see yourself as more of a S sized person or leaning towards S/M.
PS. S size kits seem to be sold out for the third and special edition.
This post has been edited by GaryTan: Feb 21 2011, 11:40 PM