I think that it depends upon your ear.
You could feel very comfortable with sennheiser ie8's big double flange, which is huge, or foam tips, depends a lot on the ear, type of ear, and so on.
The general consensus is that foam tips are more comfortable, but i found them quite the oposite, they falled out of my ears quite often, and reduced treble.
I dislike Comply foam tips, but like Monster Supertips (gel and foam) and Sony Hybrid foams.