Originally Posted by
Kiwi Flyer
Since the lounges are basically the same I'd just use the one in the departure concourse.
You have no choice : you have to use the lounge of the concourse you are departing from. By example, you are not allowed to pass security at M if your flight departs from K or L. The only exception to this rule was last summer when the K lounge was closed for renovation of the kitchens and they allowed people to go to L.
And the 3 lounges of 2E are not the same : the M lounge is more recent and has different design and furniture than K or L. And, for food, there is not yet warm options at L.