I too am going to make myself unpopular here..
I have an Apple TV 2 and while it worked okay, running Plex on it was just too unstable. Ended up purchasing a Roku and it has been flawless since. I received an Apple TV 3 as a gift from my company which I ended up selling. I've since moved my original Roku to the bedroom and have a Roku 3 on my main TV. My Apple TV 2 has been sitting there unplugged for quite some time.
I know this site is very pro Apple, and I love most Apple products, but the ATV is not one of them. AirPlay is the only thing the Roku lacks that I miss. The remote is garbage IMO and I love the Wifi Direct remote of my Roku 3.
AppleTV wasn't designed to work with Plex, its a hack, which may or may not work well.
But, to each his/her own.