I am in the market to upgrade my headphones since my wife took my $50 Sony ones back to the States with her. I was looking at a couple of pairs of Seinheiser's (PXC150,PXC250,PXC300) or a pair of Bose QC2. The Sennheisers look to be more portable. Is there a difference between earphones that completely encompass your ear or those that just cover them. The Bose ones do but it looks like the Sennheisers do not. Any feedback appreciated.

Kampai,
Klaxon