BlueAnt's new $99.95 Z9i Bluetooth headset has a lot going for it, including dual microphones and an improved version of the company's Voice Isolation Technology for noise suppression, echo cancellation, and wind-noise reduction. It can also pair with up to five devices, and like the Plantronics Voyager 520, it can pair with two of them simultaneously using BlueAnt's multipoint setup. In this mode, you can answer calls on either phone with the Z9i simply by pressing its multifunction button.

The plastic Z9i measures 1.6 by 0.7 by 0.4 inches and weighs just under 0.4 ounce. Unlike most Bluetooth headsets, the Z9i includes two large, easy-to-press volume buttons, as well as a clearly labeled multifunction button. The unit comes with two adjustable ear hooks (one translucent and one rubberized) and two sizes of earbuds for a comfortable fit. My review set was a glossy black, but the Z9i is also available in a fetching bright red.

The headset paired instantly with a BlackBerry Pearl 8130 and a Motorola Q. Sound quality was excellent in both directions, in both indoor and outdoor environments. I tried standing near several fans of varying degrees of loudness, which were generally inaudible on the other end; eventually another caller caught on when I stood next to a central AC unit outside.

The unit can switch between Standard and Max modes for voice isolation. Hold down the multifunction button during a call for one second and you'll hear the voice toggle between the two modes. However, callers couldn't hear much of a difference between these two modes; for example, the person on the other end still heard the AC unit running loud and clear at the same volume regardless of the mode, and said that with either mode my voice still sounded fine. This is nitpicking, though. The Z9i is a great-sounding headset, even if the noise-canceling circuitry doesn't quite match up to that of class leaders like the Aliph New Jawbone, our current Editors' Choice.

Oddly, if you want to switch from the headset to the handset during a call, you can't turn off the Z9i the usual way, which is to hold down the multifunction button for three seconds. Instead, you have to press down both volume buttons (+ and -) simultaneously, which takes a little getting used to. On the plus side, the Z9i has differing ringtones for contacts that are in your address book and ones that are unknown. The headset is also firmware upgradable via a PC's USB port. It supports the usual array of features, such as call waiting and call conferencing, and it can also switch back and forth between calls on two simultaneously paired devices.

Endurance-wise, the Z9i lasted 4 hours 50 minutes in a continuous talk-time battery-rundown test. That's a little on the short side; many headsets, among them the Samsung WEP700, achieve closer to 6 hours. (The otherwise stellar Aliph New Jawbone disappointed with a 3 hour 40 minute run.)

The Z9i has some tough competition. The Aliph New Jawbone's disadvantages, apart from its shorter battery life, are that it's more expensive at $129.99 and not quite as comfortable to wear. But it looks great, and its superior noise cancellation means that you'll always sound good to other callers, even in noisy environments. The Plantronics Voyager 520 ($100), meanwhile, also has terrific sound; it offers the same multipoint connectivity for using two devices at once, and its battery life is outstanding. It's quite large and ungainly by comparison with the others, though. For many buyers, that's a deal breaker. And the $100 Iqua 603 SUN is a fun one with its built-in solar cell, which means you'll generally never have to charge it—but it's not as stylish or comfortable as the Z9i. If you're looking for comfort and style from a superb-sounding headset, the Z9i is a solid choice, but it's not the only one.

More Headset Reviews: