I don't understand the guy who complained about no bass? I hear plenty of bass. In fact, IMO it's about perfect. Thumpier headphones can be fun for some music, but the amount the 545 has strikes me as a great balance for an all-purpose set. I can see why it might even be too much for some, but I like it. The KEF M500 seemed a bit clearer and more neutral, but thinner and not as enjoyable to listen to for me.
Interesting. I don't find the M500's to sound thin at all, and I find them to be incredibly enjoyable to listen to. So when I read something like what you wrote above, it doesn't do anything to lessen my interest in the 545's, that's for sure!