Right now, I personally prefer Espeon, due to all its battling skills; with its Magic Bounce ability, it's able to throw all non-damaging moves back to opponent without any trouble, making them fall under their own trap, and this, I believe, is more than helpful. It could go along with almost any team at any given time.
When generation two was still active and an ongoing thing, however, Espeon wasn't like this in at all, so it didn't catch much of my attention. I wasn't much into strategies back then, either--back then, I would rather play straightforwardly--so even if it were good, I still wouldn't have put as much attention onto it. Personally, during Gold, Silver, and Crystal era, I liked Umbreon a lot more, as it seemed very cool to me.
As for which one I chose, in my first, second, and third runs, I believe it was Umbreon. Afterward, I went with Espeon.
