Should i trade Kenny Britt for DeAnelo Williams Fantasy

[Sbot420]

I Could use a third starting RB. Do you guys think i should trade K. Britt for Williams???
Britt could end up beasting, so im not sure what to do here but im playing for about 15x
My line up
A.Luck
L. Mccoy
A. Peterson
V. Cruz
J.Nelson
Torrey Smith
T. Gonzalez
Giants D
R. Gould

and my bench is
M. Schaub
K. Britt
R. Cobb
M. Manningham
N. Burleson
K. Moreno
Tashard choice