Which Eeveelution did you choose?

It depends on the nature of Eevee. If its close to a Modest Nature (with good special attack) then I'll pick Glaceon or Vaporeon. If its a Speed-helping nature I'd choose Jolteon. I don't think the others will help me in battle though, but I usually prefer Vaporeon regardless as it easily beats Crustle at the Battle Subway Boss.

I have generally always chosen Jolteon for it's superb speed and good special attack or Vaporeon for it's identical special attack and high HP. I do think Umbreon is pretty awesome, I wish the baton passing of mean look was not removed in gen 5. Haven't actually tried to use Leafeon or Glaceon on a team to be honest. I did hear that Glaceon is pretty useless though.

I had a Jolteon the first time I played Red.

Then I had an Umbreon in Silver.

Umbreon,Cause Great Defense And Good To Stall With.

Up until 4th gen I would more than likely go with Espeon but, when Glaceon was introduced, it became one of my favorite Pokemon so I usually go with it over any of the others nowadays.

I used Vaporeon for the first time in Fire Red , I think., as my main water Pokemon.

I like all the Eeveelutions tho, but I have never used them in my team. :)

I've chosen Espeon the most out of all the other Eeveelutions. But I've used Flareon, Jolteon, Vaporeon, and Umbreon too. And one day I will find a way to put a Leafeon on a team as well as a Glaceon.

This is a hard one.... but i will go with Umbreon

The only Eeveelution design I don't like is Jolteon.
Flareon is beautiful, but in every case where I've had an option to get one, I had better Fire Pokemon available. So I never got it.
I've gotten both Espeon and Umbreon in Johto, Espeon proved to be more useful for in-game.
In Sinnoh, I went for the newer gen Eeveelutions. I bred to get both of them, I love both of their designs and they're both pretty good in battle.. It just takes awhile for Leafeon to get appropriate moves.

It varies, although tbh I don't really recall using any of them other than Glaceon and Leafeon in Platinum on separate occasions. And maybe Flareon the first time I played Platinum first time. I wouldn't say they're my favourites though...that's probably between Flareon and Espeon, with Vaporeon / Jolteon / Umbreon tied behind them.
So I guess I'll vote Flareon, Glaceon and Leafeon then.

I always choose Glaceon <3
....unless I'm leveling Froslass in which case I choose Umbreon c:

I always picked Jolteon in R/B/FR/LG because I usually needed an electric type for my team, it's also the coolest of the Eeveelutions even now there's seven of them.

I remember evolving my Eevee into Leafeon in D/P, but I never used that Leafeon anyway.

Jolteon is the only one I've attempted to use competitively on Showdown as well, so Jolteon is my choice by far.

I chose Leafeon. I think they look really cool and are actually one of my favorite Sinnoh Pokemon.

I chose Jolteon because of it's good moves and cool design. Gen II was Umbreon, no competition. It's just so much stronger and versatile.

I had Vaporeon, Jolteon, Flareon, Espeon and Umbreon in Pokemon Crystal. I don't remember their full move sets but I think these were parts of them:

Vaporeon - Aurora Beam, Hydro Pump, Quick Attack, Water Gun??
Jolteon - Pin Missile, Double Kick, Thunderbolt, Thunder
Flareon - Smog, Fire Spin, Flamethrower, Quick Attack
Espeon - Psybeam, Psychic, Confusion, Morning Sun
Umbreon - Faint Attack, Pursuit, Quick Attack, Moonlight

My memory isn't so good since my Crystal version dried up 5 years ago and I haven't played it since but I think these were their move sets I chose.

It depends on the game, really. If it's a 1st/3rd generation game, I always go for Jolteon. If it's 2nd/4th generation game, it's totally Umbreon. I find myself using Umbreon the most.

Flareon - R/B
Umbreon - G/S
Both - FR/LG

Flareon, Jolteon, Espeon, Umbreon, those have to be my favorite eevee's. I don't care too much if they are good or bad in battle, they just look awesome. Besides, right now I would do anything for a Flareon to keep me warm. I hate you Winter... ;-;

Lets be honest when I first played pokemon I had no idea what eevee was (my bro would be my source of information) until I played gold and kept it in my party it evolved when I beat chucks poliwarth (quick attack ftw) my fav type is dark but I like jolteon better =P

Vaporeon is definitely my favorite until glaceon came to be :)