I haven't tried on the Gizmo, but I have 35 days on the 2012 Judges. They haven't packed out much and still fit tight. I absolutely love them. The heel hold is fantastic. I have narrow ankles with a wide forefoot. I have zero heel lift with these boots. I figure the flex is similar to the Gizmo.
I upgraded from the the 2010 judges which have the bravo liner just like the Gizmo. They were super comfortable and had excellent heel hold. The liner didn't pack out much either. I personally like dual zone boa, as the boa wires don't loosen up throughout the day as you ride (this has been my experience with lace boots). I figure the lower boa with upper lace would be nice too. From my experience with lace boots its kinda tough to really tighten the lower area, so having the lower boa system would be a big plus.