I think Benjamin is the 3rd option at SF of those 3. I'd go with the PG if you have plenty of REB at PF and C simply because of his SPD, ATH, P, and BH. Especially if he's not going to be a scoring option, his P and BH would greatly help out whoever is going to be your scoring options. A close 2nd would be Ardoin. Go with him if you need REB help. His LP rating alone makes him better than Benjamin. But again, I'd go with the PG>