Sandwiched between the 2.8-pound VAIO TX and the 5.5-pound VAIO FJ in Sony's lineup, the VAIO SZ offers perhaps the optimal compromise between size, weight, and screen and keyboard size. At 3.8 pounds, it's not the lightest model available - even within Sony's lineup - but it manages to be eminently portable without sacrificing a readable screen or a usable keyboard. Even better, the VAIO SZ has all of the features a business user will need, from an integrated microphone and Webcam for videoconferencing to a fingerprint scanner for security, not to mention a solid array of components such as an Intel Core Duo processor and an Nvidia graphics card. Of course, as with all Sony laptops, the VAIO SZ is pricey. Though it starts at $1,400, our loaded, premium test unit costs $2,500; for contrast, the 3.2-pound Gateway NX100X costs nearly $1,000 less (though it lacks an optical drive and a number of the VAIO SZ's other features). That said, if budget isn't your primary consideration, we think the VAIO SZ is an excellent portable laptop.

With a sleek, brushed-black carbon case and a very similar profile to that of the model which it replaces, the VAIO S, the VAIO SZ runs about 12.4 inches wide, 9.25 inches deep, and just less than 1.5 inches wide. Weighing 3.8 pounds (and 4.8 pounds with its blackboard-eraser-size two-prong AC adapter), it's absolutely light enough for regular travel.

One of our favorite things about the VAIO SZ is the keyboard. Though it's not quite as firm as the Lenovo ThinkPad Z60t's and has considerably fewer keys, the VAIO SZ's keys are impressively large and nice to type on, even for long periods - a rare quality for such a lightweight laptop. Though the touch pad and the mouse buttons are on the smaller side, we found them adequate to work with; that the fingerprint scanner is placed between the mouse buttons didn't bother us, and though it's not marked, the touch pad features both vertical and horizontal scrolling functionality. There are few multimedia controls here; besides two tiny programmable buttons that sit above the keyboard, the VAIO SZ makes do with key-combination shortcuts for volume and brightness adjustments. The laptop runs very quietly and coolly.

We also really like the VAIO SZ's 13.3-inch wide-aspect display; it's incredibly bright, has excellent contrast, and its 1,280x800 native resolution offers the perfect amount of detail for the size of the display. The two small stereo speakers that sit just above the keyboard deliver unremarkable sound.

The VAIO SZ offers a cut above the bare minimum of features and connections most business users will need. For on-the-go videoconferencing, there's a handy 1.3-megapixel Webcam and an integrated microphone built in above the display. Also onboard are the standards: headphone and microphone jacks, two USB 2.0 ports, one four-pin FireWire port, and a VGA output, one ExpressCard slot, and one PC Card slot. In addition to an integrated card reader that supports only Sony's own Memory Stick format, our system shipped with an ExpressCard SD memory card reader. Networking connections include 802.11a/b/g wireless, Gigabit Ethernet, a 56K modem, and Bluetooth (WWAN connectivity will be available on the summer 2006 models); one handy switch can turn off all of your wireless connections at once, which is helpful for battery conservation. Our test unit was configured with Microsoft Windows XP Professional, and Sony also throws in its typical software bundle, featuring a solid assortment of AV apps; disc-burning software; and security, recovery, and support utilities.

Our pricey $2,500 premium VAIO SZ160PC test unit came configured with a solid set of specs: a 1.83GHz Intel Core Duo T2400 processor, 1GB of DDR2 SDRAM (533MHz), a low-end Nvidia GeForce Go 7400 graphics card with 128MB of video memory, and a big 100GB, 5,400rpm SATA hard drive. There's an external speed/stamina switch that lets you toggle between using integrated graphics (for stamina) and discrete graphics (for speed) - an innovative and useful feature that we've seen on few other models. We compared the VAIO SZ to a $1,625 Gateway NX100X (a.k.a. the E-100M), a $2,300 Lenovo ThinkPad X60s, and a $1,800 Sharp M4000, all of which weigh between 3 and 4 pounds. With the strongest set of components (and by far the highest price tag), the VAIO SZ led the pack in mobile performance; it's powerful enough to shoulder any productivity task and with its discrete GPU, even some games and advanced graphical tasks. The VAIO SZ also delivered 5.6 hours of battery life, well short of the 8.2 hours we got from the ThinkPad X60s, with its extended battery, but still competitive for its weight class.

Sony backs the VAIO SZ with an industry-standard warranty: one year of free service (including free shipping both ways) and 24/7 toll-free telephone tech support; after the year expires, support calls cost $20 per incident. Sony offers an array of warranty extensions; a three-year plan with onsite service costs $250. The company's Web site provides a good knowledge base and e-mail support from Sony technicians. Sony provides copious, clearly written electronic documentation for the VAIO SZ, though very little printed documentation - a problem if the machine malfunctions.