You are right. The Atlas Turtle Beach headset is simply an XO4 with Titanfall decals. One special thing about the Atlas however that neither the XO7 or XO4 have is that it is also compatible with Xbox 360 and PC.
The x07 and 04s have the same hook ups. they both are wireless to the console. but require hook up to controller. Both only put out stereo because of the adapter only capable of stereo but they keep saying possible surround in the future. which i dont buy for a second. if you look on the user guides for each of them on the TB website both have the same specs, speaker size etc. the only difference is that the x07 has tearaway cables and different cosmetics, memory foam etc. To me the earforce Atlas titanfall headset is the best of the 3 choices because it has the legacy 360 hook ups as well as X1 hookup so you can hook it up through a DSS and still get dolby. you will have more cable to deal with but it will still sound 100x better than the other 2. and ALL 3 of them come with the adapter just to note since i saw a couple post saying the titanfall headset didnt.
$150 for a non surround headset? Why are you considering buying these at all when you can buy the Tangos and get 7.1 surround for the same price. I don't get it. Having to tether to the controller, for starters, is an abomination in itself. Being that we have to do so, I am thinking of selling my Tangos and going with the Astro A50s, since they are a significant step up in overall sound quality.
As far as I understand, and from what's been reported from both companies, is that "TRUE surround sound" with headphones is essentially impossible. Polk engineers commented that they use their own technology to simulate it to surround sound as authentically as possible, and I'm sure TB will have something very similar. I'm sure these both will provide the surround effect.