Yes, I am a firm believe in "friends with benefits." For many years before I met my husband, I had "friends with benefits." Due to familial and career obligations, I did not have the time to commit to a relationship, but I still needed and desired the physical connection. My partner(s) and I would sit down and discuss the rules and expectations, such as if we were exclusive "FWB" or if we were permitted to have other "FWB" concurrently. There were also rules regarding discussion of emotions, keeping an "irregular" schedule of when we would hook-up, and ways to break things off in the event one of us were to develop feelings for the other.
I believe this to have been successful for me because I am not the stereotypical girl in that I am able to easily shut off all emotion in a situation and walk away without guilt or concern for the other parties feelings. Normally, this would not be a good trait to possess, but in a FWB situation, this is preferential.