Though the Z30 is part of the thin-and-light Portege line and the Z40 and Z50 are included in the mainstream Tecra series, they're basically indistinguishable, apart from the obvious difference in screen size. All of them have magnesium lids, with the same honeycomb frame that you'll find inside some of Toshiba's older machines. Also whereas the Z835 had an awkward hinge with "shoulders" that rose above the keyboard, these machines have a cleaner, more understated look. Across the board, too, Toshiba included its Accupoint tracking stick, along with backlit keyboards, fingerprint readers and larger touchpads. Finally, they all have docking connectors on the bottom, which you can use with the same dock regardless of the screen size you choose.
As you'd imagine, it's on the spec sheet where you'll find the most differences. As the closest thing to an Ultrabook, the Z30 is the least configurable, and is also missing certain niceties like discrete graphics. Here, you'll get your choice of Core i5 or i7 vPro processors, with 128GB or 256GB of solid-state storage and a battery rated for up to 10 hours of runtime. Given that these ship with Windows 7 by default, it understandably doesn't come standard with a touchscreen (none of these do), though you can get a touchscreen and configure it with Windows 8, if that works better for your company. The one thing we can't really make sense of is the resolution: 1,366 x 768 seems low, especially for a machine that starts at $1,249.
Step up to the Z40 and Z50, and you'll get the same ports (Ethernet, VGA, a SmartCard reader and USB sockets) but the specs will be more varied. Whereas on the Z30 it's all solid-state storage, here you can get a 7,200RPM HDD with 320GB to 750GB of space, as well as a hybrid drive. Also, the SSDs on these models max out at 512GB, not 256 gigs, so that's nice. Additionally, as we hinted earlier, you can opt for discrete graphics, with NVIDIA's 730M being the GPU of choice. One slight tradeoff is battery life: these are expected to last eight hours on a charge, versus 10 for the Z30 we just told you about. As for weight, the 14-inch Z40 weighs 3.2 pounds and the Z50 comes in at 3.9. Finally, there's the screen: you can upgrade to a sharper 1,600 x 900 panel on either model. Both will start at $1,199, but while the Z40 ships October 18th, the Z50 won't go on sale until late November or early December.