Pros: Very good audio quality, refined, balanced, never harsh or sibilant, "open sounding"
Cons: Small cups may be a deal breaker for those with big ears
These sound really good for closed headphones: very good detail, good bass, fantastic mids, good highs without beeing too bright or harsh sounding. Jumping from v-moda m80 I found these more detailed and extended, expecially on the highs. The sound is also more airy and the soundstage more extended.
I also owned v-moda m-100 and while I think both are very good, I find momentum best for rock genres (like muse, radiohead,...) and as all-rounder while I found m-100 best for dance, techno and electronic genres.