hi welcome to smogon, let me 'splain the current situation of ouZapdos is a less worthy option for defoging: It has weakness to SR and its kinda a setup bait for mons like Clefable. Thunderbolt + Heat Wave is cool but I think Skarmory is a more realiable defoger for OU.
skarmory is, on paper, better. however, skarmory gets trapped and murdered by magnezone, opening up holes for monsters like mega pinsir to sweep uninhibited. this is a problem because magnezone is all over the place at the moment, so skarmory is having a tough time doing its job. zapdos does not get trapped and checks mega pinsir, which is a massive boon over skarmory.