I’ve got two, both which I bought new from Apple and jail broke myself.
At the time they were £100 each and jail breaking is only a 10 minute job. I guess the 2nd gen ones are carrying a premium now because you cant jailbreak the current (3rd gen) ones. They are great as a silent, easy to use, set top.
Main thing to bear in mind with these Apple Tvs is they have no storage. Your content must be served from elsewhere, either the Internet or somewhere else on your network. I have a Mac Mini running Plex media centre that serves up the content to the Plex app running on the ATVs. All the content is actually stored on my NAS. Out of the box, non jail broken, your expected to have a similar setup using iTunes as the server and content library.
The ‘freeness’ is slightly over stated by that EBay ad. Very little of the ‘free’ content mentioned is legal if such things bother you.