Question about online dating sites?

I haven't had any in about 6 months and am beginning to get restless.. don't have any girls i can call up and just mess with.. i'm 25 years old, tan skin, in great muscular condition, just was in a long term relationship and lost touch with many of the girls i knew. but i need a piece now. would you recommend dating sites for a quick hit and quit? Fat chicks will do at this point (140-170 pounders, no more then that though)