Hm... Well, it turns out that my ears are deceiving me XD The measurements for the Phiaton Bridge are up on InnerFidelity: http://www.innerfidelity.com/images/PhiatonBridgeMS500.pdf
They look similar to the M-100, for all intensive purposes, they seem closer to what I was expecting the midrange of the M-100 to sound like: http://www.innerfidelity.com/images/VModaM100.pdf
Overall, I actually still prefer the Phiaton over the M-100. Quick note though, this one on comfort, the proper placement with these is a little more tricky, once you get it, these headphones Will be more comfortable resting on the ears. Phiaton says these are over-ears, with the proper fit placement, they are. They may not fare too well with small ears. The pads are thicker, and softer than the M-100, but the overall size is a lot smaller. Tyll has classified them as on-ear, I can get them to fit over the ear though, but you have to place them precisely or it won't fit over-ear properly.
Sound-wise, these are very strong contenders. The bass still has a low-bass emphasis create stronger, thicker impact. Actually, the bass as a whole is a lot thicker. Texturing is there, but does not give the fluidity that it should being a little too solid. The midbass punch is there, but can be a bit overshadowed by the lower-bass; it's also not as tight as most would like. The midrange has ample detailing down low, the headphones aren't aggressive in any way about details. The upper midrange clarity is very strong with these while vocals can shine in both the lower and upper octaves. Treble overall has great extension throughout, separation and detailing remains strong in the upper treble. In the lower treble, presence seems a little lost at times. Require more detail? Wait for the whole review XD