I use them both. I typically use the speed down debuff on phasma first though, which means the first use of Lando's special is up to RNG. It typically pays off, which means round 2 is awesome. Usually by the time I use it the second time, QGJ has dispelled too, so now I'm blasting it with Offense Up, Advantage, and if for some reason opponent has Lando in the yellow, I get a bonus from STH's leader skill. Lando becomes the ultimate power in the universe.