It may take a while to Raikou come to the game, so Zapdos seems a solid option against water and later to Ho-Oh, but Charge Beam is so underwhelming on attack? I haven't use it so I can't compare it to TS
Is Charge Beam bad?
It is designed to be a high EPS and low DPS move. But it falls below the EPS-DPS efficient frontier - Fury Cutter has both higher EPS and DPS, for example. Anyway, the point of high EPS move is to launch Charge attack more often. Zapdos's Thunderbolt is very fine as a charge move, so I think Charge Beam is not THAT bad.
This is likely the feeling left from discussions of Amphoros versus Jolt.
The difference being Jolt was made much better by having TS since he really needed to dodge due to his glass cannon stats.
TS is still superior but with the added bulk and even better damage on Zap it's much closer. While TS would still be a better move ( roughly 10% more damage and very comparable energy gain) the loss of the serious dodging ability isn't that huge.
TLDR: I would prefer TS but CB is close enough for this mon to make little difference IMO.
For me Charge Beam felt way less intuitive than TS, which is why it felt way inferior to TS, too. But after getting used to it (~150 Fights with my maxed out Zapdos atm) it's getting better and better.
Under the aspect that a lot of Damage is coming from Zapdos Charge Move the gap between CB and TS is small. It "feels" small and on paper it's small, too.
I am pretty satisfied with my Zapdos and i am not regretting the stardust i have invested, even if raikou would come tomorrow, no regrets! I simply love my thunder chicken :D
