In terms of whether or not an EMBA has the same value, it all depends on what you're looking to get out of the program. If you want the brand name of a school like Columbia behind you, then either is fine. If networking opportunities are what you're after, a full-time two-year MBA will give you more opportunities there (simply because it's a more involved program). Overall, in your case, I think you'd still get the benefit you want from an EMBA program.
Harvard does offer executive management training, but it doesn't offer a straight executive MBA. It's more of "a class here, a class there" kind of thing. But Columbia's program could be a good one for you... Definitely should look into that one more.
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