Here's my wrap up of the One X series...
AT&T:
Reported to be getting the One X without the 4+1 Tegra 3 processor due to LTE network incompatibility.
Instead it will have the S4 Snapdragon/Qualcomm 1.5GHz dual core processor inside (which might not be a bad thing) & run hTC sense 4.0...
Sadly, AT&T's HTC One X won't be quad-core (and here's why) | Mobile World Congress - CNET Reviews
Tmobile: (Rumor)
Tmobile is said to be getting the One X with the Tegra 3 4+1 core processor to run on their HSPA+ network. Rumored to be running stock ICS "vanilla" UI.
They will probably brand this device as a "G" series phone...
T-Mobile variant of HTC One X said to have quad-core and stock Android 4.0
Sprint: (Rumor)
Also said to be getting the One X, or maybe a variant, called the hTC Jewel. They will probably brand this device as an Evo HD LTE. It will have the Tegra 3 4+1 core replaced (like AT&T's) with the Snapdragon S4 1.5GHz dual core processor & (more than likely) probably run sense 4.0... Link in article above as Sprint, too, is expected to offer a version of the hTC One X...
Now with Tegra 3 4+1 core vs. Qualcomm Snapdragon 1.5GHz dual core processor...
From what I have been reading/seeing it suggests that the S4 outperforms the Tegra 3 in most cases and even blows it away...
A Preview of the Krait-Based S4 Vs Tegra 3 and Exynos 4210
" The whole idea of 28nm and big little design of A15 chip is to provide better performance at a much lower battery cost. So the idea that Tegra 3's 40nm (pentacore) chip will be more efficient seems invalid. Real life usage will tell us more.
In short A15 > A9"
Well, that's what I may have learned and what I think I know about the hTC One X series.
A lot of this are rumors/speculation, so we will all see how it all plays out, with no removable battery and absence of sd card slot included!...you are now free to complain about that for the rest of the thread!