Is changing a friendship into a sexual friendship without any strings a smart move on my part?

For more than 10 years I have been friends with this guy and for the most part of our friendship, on occasion we have gotten more intimate (completely initiated by him), but it never progressed to anything more, just back to friendship.
I did confront him once about taking it further, but he just told me that he wasn't the relationship type. Even though I did get very fustrated and angry with him at that time, several years later, I have now gone and proposed to him that we become sexual partners with no strings attached, which he very happily agreed to.
Since then, I call him up and he comes over, sometimes for a whole night and others for a quick meeting. So far it is always me doing the initiating. At times I do feel very strongly that he has more feelings for me, but he never tries to take it any further.
Even though I do like him and would like for it to go further, I enjoy the sex with him. I do fight my feelings often, since I do like him more than that and I know he dates other women.
On the other hand, I do enjoy the freedom of the "no strings" and the benefits of the sex!