With Windows 8 turning Microsoft's flagship operating system into a hybrid system that melds both mobile and desktop interfaces, it's perhaps not surprising that PC makers—led here, too, by Microsoft—have moved to hybrid designs for their own devices. Heading into 2014, the market for these devices is maturing along with Windows itself. Is it time to consider a hybrid, or "2-in-1" design? And if so, how do you choose?

The term "2-in-1" is a bit loaded. It refers generally to the fact that these new kinds of PCs have (at least) a dual purpose, in that they can be used like a tablet or like a traditional clamshell-type portable PC. But as is always the case, things are more nuanced than that, and many 2-in-1s actually feature more than two use cases, the Lenovo YOGA lineup being a prime example. I typically use the term hybrid PC to describe such devices for this reason.

But whichever name you prefer, the idea is at least as sound as the OS software that inspired such an approach. Which is to say, very sound or not at all sound depending on your perspective. And of course on the success of whatever hybrid PC design you're currently evaluating. Ideally, such a machine would be a "best of both worlds" scenario, in which it was both a viable laptop and tablet, depending on configuration. But many of the first and second generation 2-in-1s could hardly be described in this way.

There's also an interesting discussion to be had around the approach such machines can take. Here, as is so often the case, I find comparisons from the automotive world to be helpful. That is, if you accept that a PC is like a truck and a tablet is like a car—as Steve Jobs infamously pointed out at the original iPad launch four years ago—then a 2-in-1 is a like a crossover vehicle. And if you know your cars, you know that some of those kinds of vehicles are built on car platforms while others are built on truck platforms.

Over-simplifying things dramatically, the car-based crossover vehicles tend to be smaller, nimbler, and more comfortable, while the truck-based versions are more durable, more powerful and less efficient.

With this in mind, consider the hybrid PC, or 2-in-1. Some of these designs are clearly PC based, with a traditional clamshell-type design in which the screen can fold back over the device so that it can be used as a (slightly thick and heavy) tablet when needed. Others, based on a tablet design, put the guts of the PC behind the screen so that the screen part can detach from the keyboard and be used independently as a tablet.

As you might imagine, each offers some compromises. Some pros, some cons.

Tablet-based 2-in-1s like the Microsoft Surface products, the Dell Venue 11 Pro, HP Envy X2, and many others tend to offer smaller (sub-11-inch) screens, since a large-screen tablet would be heavy and awkward in use. For this reason, I find most of these types of PCs to make for better tablets than PCs, since their small size makes using them as a laptop less than ideal. There's a reason Ultrabooks start at 11-inches and move up from there.

On the flipside, PC-based 2-in-1s tend to work better as PCs than they do as tablets. This is because the resulting design—in which the screen and keyboard are never separated—is heavy and can be awkward to hold. Depending on how the thing transforms, the keyboard is often oddly found on the outside, on the back, when the device is used in tablet mode.

As with the crossover car comparison, what this comes down to is how you'll use the device most frequently. That is, if you're going to spend most of your time—as I will—working in the desktop environment with a keyboard and traditional pointing device (mouse, trackpad), then a PC-based 2-in-1 with a larger screen is the better choice. But if you think you're going to spend most of your time using the multi-touch-based tablet interface—what I still call "Metro"—and only occasionally dip into the PC side of things, then maybe a tablet-based 2-in-1 is the better option.

I write "think" and "maybe" there because we've learned a few things over the past year about these kinds of computers.

One, people aren't buying them. The vast majority of PCs sold in the past year are still traditional form factor devices without multi-touch. And while Metro is at least usable on a traditional PC, using the desktop from a tablet or tablet-based 2-in-1 is, shall we say, less than optimal. Especially on the smaller "mini-tablet" designs that gaining steam.

Two, you may not really know what you want. The truth is, very few people have actually spent any time using a multi-touch Windows tablet running Windows 8.x, and the jury is still out on whether such an experience is desirable, let alone viable. I've probably used Windows 8.x more than anyone outside of Microsoft, and while I do have access to a shocking number of Windows tablets, mini-tablets and 2-in-1 devices, so far I've stuck largely to my traditional, non-touch desktop PC and Ultrabook. And I've tried.

I'll be trying more. This year, I intend to focus a lot of time and effort on this device category and will see whether any of the newly-released designs speak to the coming successes of both Windows and the new devices on which it runs. I have some ideas about the devices I'd like to review, and will be reaching out to PC makers for loaner units in the days ahead. But if you have any thoughts about particularly well-designed Windows-based 2-in-1 PCs, tablet- or PC-based, please do let me know. It's time to figure out whether this direction makes any sense at all, and if so, which devices are truly worth considering.