I dont think you can judge it by stats.... ive had good days where i get 20-0 one round after another, but ive also had bad days where i cant get any hitboxes and i die alot, theres also more issues to think of such as a slow server, your home connection issues, ping, lag, etc.
If you had a sniper match of say DBSS vs some n00by to bf2 itself, and DBSS had major connection issues and a 300 ping, and the nooby used this to advantage and won, you couldnt say this n00by is better at sniping than DBSS, could you.
I think in REAL IO, ie no vehicles at all, snipers vs medics, snipers would win, but on a foggy map such as karkand, on usa side with no dragunov, medics FTW.
Put them both on dailian or wake and its a different story.
As for supreme snipers in bf2, the best ive come accross are
EMPTY-06
Sarciss
Todd Angelo
sn][per member, i dont remember his name, hangs out on h911 alot
DBSS
Janis Petke
thats about it from the top of my head.