I bought this unit for cooking our Christmas prime rib and fortunately I had kept my old remote temp unit.  Used the #1 port and the unit flat lined at 70 degrees for the first 1 1/2 hrs.  Put probe in the #2 port and temp went up to 105.  Put the probe for my old unit in the meat and it showed 120.  The Weber temp finally got to 110, old unit 125, pulled the meat and it was perfect 125 med-rare.  If I had used the iGill 3 until  it got to 125 the meat would have been well done!!  Will use it again to see how it does but I will definitely have a back up!!!