It's truly a toss-up between Lawson and Kowalski, but we're giving the edge to Lawson for no other reason besides strength of schedule and his week to week partners(meaning Marinelli).  

We looked through random tournament results to see if Romero and Rahmani have met, but could not find any match-ups between the two.  Romero lost to Kowalski by one at Ironman and Kowalski also missed placing, along with Rahmani.  

Overall, Lawson is the #1 until someone beats him.