Using ModMic doesn't differ any from headsets... except that you can easily detach mic when not needing it.
(even swap it between two headphones, there's second base included)
Directional v4 muffles quite nicely for example keyboard sounds.
Active noise cancelling headphones are expensive if any better and still compromises in sound quality compared to normal headphones.
Some closed headphones actually isolate basically as well as weaker earmuffs.
Like Beyerdynamic DT770s from 15 to 20 dB at mids, nearing 30 dB in treble.
So unless environment is really noisy those would go long way.
For price those also would be quite good for gaming use with good positioning and decent soundstage for closed design.
Though for competitive gaming they could use equalizer for toning down bass.
(which still doesn't drown everything else unlike in typical closed bass heavy gaming headphones)
Design of Beyerdynamics is such that they can be also mic modded easily:
http://imgur.com/gallery/bKU4H