Painting - Do "flat" and "eggshell" look the same?

We like the way flat looks and also know it's not good for high traffic & potential wet areas. Someone told me that if you use eggshell it will appear EXACTLY the same as flat finish paint, but clean up better because of the enamal content. My wife hates satin finishes, so I just want to make sure I'm not taking a step in the wrong direction if I heed this advice. Does it actually appear as flat as "flat"?

Your going to get yourself in trouble listening to someone.I to like flat paint but am getting used to eggshell.When viewed straight on most eggshells will appear flat.If there is a window or lighting that hits the wall there will be a little sheen.There really aren't many options if you like a flat finish.I have had mixed results with Sherwin-Williams Everclean.The lighter colors do resist marks and will wash without showing to some degree but darker colors not so well.

Well someone is actually the true value guy who we know. o.k., that helps, it's appears fairly flat but a bit of a sheen in the light. we'll probably go with flat except in the kitchen and bath.