Hi mate!
I am using MXR 6-band EQ and run it through the effects loop for some specific sounds and I am very satisfied with it,very transparent piece of gear and has just the right frequencies,nothing too fancy or overreacting,just what I need.Boss GE-7 is also not the bad EQ,I had it few years ago and it's decent but somehow I prefer the MXR more (though I have to admit I am long time mxr fan so maybe I can be a bit more subjective

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Floor or rack unit?
It depens what are your neccesities and needs.I would go for pedal version because I don't really need many arrays of sounds neither I rely on it as a really important thing in my setup.It just basically brightens my sound for some clean work or lead work when I need that extra twang and that's about it.
But I am long time pedal user,and If I had rack I would probably go the rack way with the eq as well.
cheers!