I have the Peace Octos- mid-size.
They have a more pronounced rim- the Tamas don't stick up over the edge much but the Peace drums present more of a rim to avoid.
They sound a bit more metallic to my ear, not quite as boingy as the Tamas.
Also, the Peace Octos mount with a large post, not the slide-in clip type like Tama. In fact, they can be a bit of a pain to position because of the mounting system.