One of those wins was at featherweight and one flew in the face of the way the fight was viewed by almost every media outlet, Fightmetric, Compustrike, etc.
Penn faced better competition over all and his victories were more impressive in form and fashion. Finishes over Gomi, Pulver, Uno, Stevenson, Sherk, Florian, Sanchez and all but one of his losses (Edgar II) were questionable, plus he avenged his loss to Pulver emphatically. I'm a huge fan of Frankie Edgar but BJ has the better resume at 155.