Would you keep any 100% IV Pokémon?

I think it comes down to personal preference. I delete any Pokemon that I don't take down, build up or defend gyms with. I get annoyed when I am trying to build up a gym and my Magmar is using a fighting move against an enemy Exeggutor.

Why would you transfer it? Do you really need that 1 Ponyta candy? I don't think so. It is really a shame that it got that moveset but it is still a 100% IV's Pokemon. Even if it got the best moveset you probably wouldn't use it anyway. Maybe when trading comes someone will want it and you can get a nice Pokemon in exchange. Maybe TM's or some method to change your movesets will be implemented. I would definitely keep it.

I keep all 100ivs. I got a nice little collection, even the crappy ones. Kingler, fearow, arbok, 2 ratticates,onix etc. Most of the game is collecting right?

I absolutely keep any ? IVs, and just organize my dex accordingly. Being at a higher level, I value these a lot just because of the time invested and sheer quantity of catches/hatched they require. I'm personally working on getting all of these to level 30. Something to work towards.

I would not keep it . I would not use Rapidash in any case. Maybe if you get one with Ember Fireblast with a good IV (be it 91,93) you would keep it I guess.
enjoy have fun.

imo I think a 100% IV Pokemon is more valuable than the 1 candy you're transferring it for. I keep all of mine even if they don't have good movesets after evolution just because they're rare. You can always save it to trade later I'm sure someone will want it.

I keep them all, with the hope that in later versions they will introduce HM/TM to change your Pokémon moves.

As you see from the different responses, it all comes down to whether you get joy from having a 100 IV pokemon even if it's not useful in battle...

And only you can answer that.

I had a 100% Magikarp, it was with Twister. instantly candified, no regrets! Moveset is much more valuable than IV, atleast to me, a perfect pokemon has the perfect ms, trying to get better IVs usually, or atleast getting 15 atk. Perfect IV and crap moves is still crap!

I keep all my 100% IV mons regardless of moveset well because it's 100 IV and rare. And out of that I power up the strong species ones that got perfect move set offensively or defensively to the max.