Jawbone Era (and Icon) work like a dream. Interesting enough, that it can connect simultaneous with the iPhone (yes both at the same time), so you could use it for Skype/Viper on the iPad and have the iPhone standby at the same time.
The Noise-Assassin technology is by far the best I have seen so far. I talk a lot on the phone, when I'm driving and the other caller very often doesn't even notice, that I'm not in my office.
Battery status is displayed in the iPhone's display and volume is adjusted via the switch at the iPhone (or on the Jawbone Era).
And NO - I'm not working for Jawbone and I'm not reselling it
Just love the thing - it is, in my eyes, by far the best headset in years money can buy.