It is possible that the sound is much clearer without EAX because EAX introduces echoes and distortions that would be present in a real urban environment due to the geometry of the structures around you.
With EAX switched off, you're going to always hear the sounds exactly as they are generated, and in the exact direction they are generated from.
It depends on what sounds good to you, I suppose. There are games, I am sure, where the EAX implementation is flawed though. Perhaps GRAW 2 is one of those. I have RB6 Vegas, and though I haven't tried playing it with EAX off, I find the sound phenomenal.