We tested the BlueFox Extreme BF-401 with the Apple iPhone 3G. Overall, the BF401's audio quality was quite good. Since the earbuds do not seal the ear, you don't get a very full bass effect. However, just for the purposes of running or working out, they work great. Since the earbuds don't seal the ear, you can hear environmental noise, which is good for avoiding traffic if you're running outdoors.
The BF-401's call quality was a little more mixed. Its incoming audio quality was great; we heard our callers loud and clear with hardly any static interference. However, on the callers' end, they said they heard a bit of background noise, despite the headset's noise-canceling properties. Even in a quiet office, they said they heard an echo. When we were outside, our callers said we sounded a bit of muffled and sometimes the ends of our sentences would cut off. This wasn't consistent, though, and some callers reported that we sounded excellent.
We're happy that the BlueFox Extreme BF-401 has multipoint connectivity. This feature lets you connect up to two devices simultaneously, for example a music player and a cell phone. When a call comes in, the headset is smart enough to pause the music and go to the call. When the call ends, it'll resume the music. The BF-401 is, of course, A2DP compatible and it supports AVRCP, which lets it act as a remote control for your music player. Some phones don't fully support AVRCP; for example, the iPhone will let you play/pause but not change tracks.
Other features include the capability to answer, end, and reject calls; last number redial; call waiting support; and the capability to transfer calls from the headset to the phone and vice versa. The BlueFox Extreme BF-401 has a rated battery life of 7 hours music playback, 8 hours talk time, and 5.83 days standby time.