I definitely say that fwb's don't work.... I have a friend who first hooked up with a guy... then she became an fwb with the guy.... lasted a year... they were always very close.... since they were always together, I got to know the guy as well.... became a good acquaintance.... and then my friend got a bf.... and omg the fallout... they both realized they were more attached to each other than they originally thought (the guy more so than the girl).... my friend cheated on her bf with the fwb.... and after that they called of the fwb status.... for the next year they would find ways to make sure they never met up again.... then a couple of weeks ago the fwb guy spared in my soccer team.... and I accidentally told my friend.... and my friend hasn't spoken to me since.... :(
so i say from experience... don't do it..... it'll eventually come back kick you in the behind.....