Yes, they are expensive, but worth it to me for the sound quality, features and build quality.

How well does the passive sound isolation work? Does it work well enough to use commuting in an urban environment? How does it hold up against ANC?

@mattykam - it's excellent as far as on-ears go. You'll still hear loud noises, as well as background noises like airplane engines. ANC is designed to block-out steady noises like engines etc, so it's a different kind of experience. ANC is important if noise-cancellation is your most important priority, or if you're a frequent airline traveller. If musical SQ is more important, passive is probably more appropriate.