Should I?

This
https://pokemongo.gamepress.gg/q-a/use-zapdos

Hundo legendaries make sweet bragging rights if nothing else.

A few points to consider:
- Electric isn't in high demand at the moment. Do you have other things that would be better suited for the dust?
- Rare candy cost; how many Zapdos candy did you rake in vs. how much rare candy do you need to spend to max it?
- Do you already have a powered up Raikou, even if it isn't maxed?

If you've considered all of the above and are still feeling it then I'd say go ahead. Personally I have a 98% shiny weather boosted Zapdos that I'm holding off on until electric becomes relevant again.

I would slowly max it out. Set goals. For example I am saving up stardust. For every 100,000 more I hit I will power up a Pokémon once. So be the time I have a couple million more, it will be maxed out.

I would