I never really liked the Eldritch Knight prestige class in the DMG.
For your “loss” of one or two spellcasting levels, you gain some HP and your BAB increases a bit. At the same time, you get a high Fort save upon taking levels in the prestige class, which means you probably won’t have any really high saves because arcane casters tend to have crap for Con scores relatively speaking.
While the pre-reqs weren’t hard, you had to either lose a level to a melee class or drop a feat to gain martial weapon proficiency. Your target starting level was 5 or 6. While you can’t start down this path any sooner, there’s some important note of other classes that supplements have introduced that may be a better fit for a prospective Eldritch Knight than a sorcerer or wizard.
I still don’t think I’d end up building a character around this prestige class. But there’s a new article up on The Wiz about the Eldritch Knight that’s worth a look. The flexibility that the PrC offers may be something that’d be useful for an NPC or a bard-esque generalist support character.
Either way, it’s worth a quick read if you haven’t given the Eldritch Knight some serious thought.