This has come up before. The Headphonia guest reviewer seems to have some sort of agenda and is banned from Head-fi to the best of my understanding. I don't always agree with Tyll's reviews but I do always respect his extensive knowledge and objectivity. My two cents is that the M-100 is the best sounding bass-heavy headphone I have ever heard.
Which guest reviewer are you referring to, Craigster? Is it Edd Noble? What's his story?
The Headfonia review reads like a sad review of a $30 bass cannon headphone, and not an M-100. I'm sure the bass is strong, but not "monstrously powerful thumping bass". I'm not aware of the reviewer's agenda, but his take on the M-100 seems to be overtly negative.