I can fire:
- consistently 3 SE with a maxed Golem vs. Thunder Zapdos
- a few times I did 3 vs. Zap cannon and I think Thunderbolt ones
- 2 SE with a level 30 one vs whatever charge move.
- quite a few RB with a level 30 one (maybe only RB as you said, but I did not payed such attention :) ).
But pokebattler disagrees with you, at level 30 a full set of SE Golem finishes Zapdos with around 30 seconds faster (related to the 820-850 total seconds needed to finish one in their simulation setup).
So SE one is around 3% faster than RB one at level 30.
https://www.pokebattler.com/raids/defenders/ZAPDOS/cp/42691/attackers/attackerLevels/30/strategies/CINEMATIC_ATTACK_WHEN_POSSIBLE/DEFENSE_RANDOM_MC?sort=OVERALL&dodgeStrategy=DODGE_REACTION_TIME#results (make sure to select No dodging and level 30 pokemons).