The HKT450 is also A2DP and AVRCP compatible, meaning it can stream music in stereo wirelessly. The Mute/Mode button doubles as a Play/Pause button when your phone's music player is activated. Samsung warns that certain phones require you to press the Mute/Mode button to activate the A2DP functions, and indeed that was the case with the Verizon Wireless Blitz. Some phones might not require you to press the Mute/Mode button, while others might need you to tweak some settings on the phone itself. We dislike this sort of unpredictability, but understand there might be technical limitations.
Another feature of the HKT450 is a "privacy handset mode" (patent-pending at the time of this review) that lets you use the HKT450 like you would a cell phone. During an incoming call, simply press the Mute/Mode button and the volume and sensitivity of both the speaker and the microphone will adjust so that you can hold the HKT450 next to your ear like you would a regular cell phone. We're not entirely sure why you would want this--perhaps you want to talk privately, but your cell phone is stashed away in a bag and you don't want the hassle of digging it out. In any case, it's a nice option to have if you need it.
Call quality is certainly impressive, but with a few caveats. Callers said they could hear us loud and clear most of the time, but there were moments when loud engine noise could drown out our voice. On our end, we could hear them just fine for the most part, though voices sounded a bit tinny and hollow. Similarly, audio quality from the phone's music player came through with plenty of volume, but was lacking in bass. That said, most portable speakers are like that, so it's not a deal breaker by any means.
The Samsung Portable Hands-free Speakerphone HKT450 has a rated battery life of 8 hours talk time and 320 hours standby time.