As with regards to isolation I have been using Momentum's for recent three weeks. I used them in airplane, one the beach, at the pool, in the train. I driven them by N900. Normally I listen at -22dB volume setting. It works well in most cases also in train. In the plane I had to change setting to -16dB, and it was very loud for my ears, and I could still hear plane engines (yeah they are loud).
The comfort of these is limited. You cannot wear glasses. My ears are in big pain after whole day of listening, and this is because ear-cups are not big enough to fit my big ears. I also fee some weir tenderness in my ears, probably caused by low frequencies.