so I just upgraded a month ago to the 4K third GEN from the HD 2015 and tbh the 2015 was still a champ love finally having 4K content but there really is not that many differences from an Apple TV released 10 years ago to today. Just being honest.That's pretty wild.
Honestly, if you're still using one of these you really should upgrade.
I found that model to be slow and "meh" even when it was pretty new.