The nice Drew Baird man at Moon has not been apprised of the the raison d'etre of the M8, or he wouldn't have pointed you in the direction of the T5p, which is basically at the top of the food chain for 32Ω impedance easy-to-drive headphones for portable rigs, which generally are capable of analog signal outputs in the neighborhood of 500 mW or less. The T5p is a very nice headphone with good sound isolation and sparkling mids, but not fatiguing (I have a set), but you don't need them with this particular (trans)portable DAC/amp setup. The M8 has been developed with enough output power to purportedly drive all headphones except maybe the most demanding Hifiman planar magnetic models. And of course Stax.
The T1 may be the better choice for matchup, since it has a bigger following and ostensively a flatter frequency range response. I assume the slightly forward mids are still there, since that may be the beyerdynamic house sound.
I use the LCD-2 at home, and I love them for their extended and controlled bass response, as well as fast and articulate response to transients. The Audeze headphones are noted for their flat frequency response over the full range, altho the mids may seem a little dark, tho certainly not at a level that distracts from enjoying the music in any sense. The LCD-3 is of course the flagship model, so I would anticipate even faster response and transient definition, and tighter bass control at the lowest frequencies due to its lower mass driver diaphragm, as well as other technical enhancements (magnetic density?). And altho it is a planar magnetic headphone as well, I don't expect any difficulty in pairing my LCD-2s with the M8. The Audezes are reportedly a lot easier to drive than the Hifimans.
You mention only the top end dynamic and planar magnetic headphone models. There are a lot of good mid-price range headphones out there that may be better suited to your budget; the Sennheiser HD650 with its large devoted fan base to name one. But others can speak more knowledgeably about these choices. And cables do make a difference. Good luck and happy hunting.
Edited by jacal01 - 4/11/13 at 3:22pm