Should I upgrade? HTC One X versus the Nexus 4

Welcome to Round 2 of our "Should I upgrade?" series. We've already taken a look at the obvious -- the Samsung Galaxy Nexus.
So let's move on to another of the flagship devices of the past year -- the HTC One X, and perhaps the new and improved HTC One X+ for good measure. (And you can basically apply all this to Sprint's EVO 4G LTE as well.) It's the pinnacle of the 2012 rebirth of HTC and packed quite the hardware punch, with HTC's usual design chops as well.
So let's break it down: Should you upgrade to the Nexus 4 from the HTC One X?

External hardware

It's almost night and day here. The HTC One X is one big slab of polyc arbonate. It's beautifully designed -- HTC's certainly no slouch in that department -- but over time I've grown weary of the plastic. Part of that has to do with my having a white One X. It just gets dirty. The gray version has no such problem, though it still shows some scuffing. (The new One X+ with its soft-touch coating is freakin' gorgeous, though.) The back of Nexus 4, while beautiful with its glossy cover and "Crystal Reflective Process" design, is prone to scratches, but it's just so much more visually appealing.
The HTC One X has probably the best display we've used all year, with its 4.7-inch Super LCD2 panel. Images are almost floating on top of it, and we challenge you to spot an individual pixel. The Nexus 4's IPS display comes close -- very close -- to the One X in terms of viewing quality, but there's something about the display (polarization, I think) that gives it a strange shimmering effect when you tilt it. That's not anywhere near a showstopper, bu t it is noticeable.
The HTC One X has capacitive navigation buttons, whereas the Nexus 4's are on the display themselves and can disappear if an application calls for it. Save for Motorola, other manufacturers have been slow to adopt the on-screen buttons, and it's caused inconsistencies with application design. I'm going to call that one a wash. Both designs have their merits, and both have their issues.
Edge: Nexus 4

Internal hardware

This is where things get interesting. On one hand, you've got the original One X, with its original quad-core Tegra 3 processor running at 1.5 GHz, or a dual-core Snapdragon S4. (Depending on whether you've got an LTE radio in your p hone). The newer HTC One X+ bumps things up to the AP37version of the Tegra 3 system on a chip, still with 1GB of RAM. But storage is being offered at 64GB, which is great considering the phone doesn't have a microSD slot.
If you've got an original One X, the Nexus 4 will be a pretty decent bump up in the specs department, with its quad-core Snapdragon S4 Pro processor and 2 GB of RAM. If you've got the One X+, it's not going to be as big a leap.
Edge: Nexus 4, if you've currently got an original One X; a draw if you have the One X+.

Lifespan

Let's face it, a few previous HTC phones didn't cut the mustard (looking at you, ThunderBolt!). But the One X is solidly built. After 6 months of solid use, I don't have any major concerns about mechanical breakdowns, aside from the odd cosmetic blemish. And while we have to wait on empirical data, I still have some serious concerns about the longevity of the Nexus 4's glass-like back.
Edge: HTC One X

Software

A lot of people like to hate on HTC's custom user interface, called "Sense." And that's cool -- to each his own. But to dismiss it without tying Sense 4 or the newer Sense 4+ is to miss out on some great features, some great design -- and slower updates to the operating system itself because of it.
The original One X line is just starting to get upgraded to Jelly Bean. The One X+ ships with it. But neither looks to have Android 4.2 anytime soon, whereas the Nexus 4 is the first (for obvious reasons). I've got no idea how many of the front-facing Android 4.2 improvements HTC will implement. It's got its own version of wireless display sharing in MediaLink HD, so Miracast may be a moot point. HTC has shunned quick settings in recent versions, so there's no promising that it'll implement Google's new version of them.
Edge: Nexus 4, untilHTCfinds a way to engineer updates more quickly.< /p>

The camera

The HTC One X has a great camera, thanks to its sensor and ImageChip processor. It's got filters built in as well. The Nexus 4 camera doesn't appear to be quite as good, but it's still above average. (And we're still waiting on final retail software before passing final judgment.)
But the Nexus 4 has the cool new "Photo Sphere" 360-degree panoramas built in. That's not to say there aren't third-party apps that can do the same thing, but Photo Sphere is already on board, and it shares wonderfully to Google+.
Edge: If you have to have Photo Sphere, get the Nexus 4 (or hack it onto your One X). Otherwise, the One X has the edge, but just slightly.

The bottom line

Six months after its launch, the HTCOne X remains a very viable Android smartphone, and the One X+ breathes new life into the line.
If photos are your main concern, you can't go wrong with either one, but I think HTC's got the edge here. On the other hand, Photo Sphere is pretty damn cool on the Nexus 4. (Oh, and if you're into the audio thing, don't forget that the HTC One X has Beats built in.)
Pricing is another thing to take into consideration, though. If you're looking to buy SIM-free, the Nexus 4 costs nearly half as much. That's hard to argue with. If you're looking to upgrade and sell your HOX, chances are you can recoup a good bit of the $299 or $349 cost.
For my money, if I had an HTC One X in hand, I might hold off on upgrading just yet. It's still a fine, powerful smartphone. The glass back on the Nexus 4 is untested in mass quantities, both phones are pretty equal in the camera department, and the HOX should se rve you well for more months to come.