These £15 JVC plugs are pretty good for the money, they come with two sets of marshmellows.

Theyre pretty good at killing outside noise and likewise if you sat on a quiet train with these on you wont get dirty looks. Very bassy, but if you push em too loud on a decent hi-fi they distort easily. Theyre pretty flat mid to high but nothing a bit of eq cant sort.

shure headsets < cheap options.