The unit does go into a low power 'sleep' after you've moved far enough away from it. If you're car is within 30 feet of where you are it will likely stay connected. This happened to me just the other day. Once you're back in the car just tap the call button and it will wake up and connect to your phone.
This is one item that does not disappoint.. It even has a low power audio warning. I usually charge once a month and use daily. Commute is about 20 minutes each way, and another hour daily driving. One of it's best features. Best part, it uses the same charger as most phones, so if you have a car charger, you are set.
I would say yes because the sound quality is very nice. You can turn the volume up and down. I use it a lot with my windows down and my sunruff open and I can hear fine no one have ever made a comment about the noise.
When you use this device you pair the phone via Bluetooth to the Cruiser, then it acts as a speakerphone. The Cruiser has a FM transmitter so you can then have your phone's audio piped through the stereo, however in my experience I turn the FM off during calls and use the Cruiser standalone for the calls. I only use the FM for music.
I am guessing you are asking if you can use Voice Command calling? If so, no this unit is not able to do that. It does have Last Number Redial that will dial the number of the last outgoing call.
Also if you plan on using the Bluetooth feature for playing music from an iPhone it can have problems with skipping. Go to this web site for more information on this unit. http://www.jabra.com/products/speakerphones/jabra_cruiser2/jabra_cruiser2 It will tell you who is calling from your contacts or tell you the number. For the price and quality you can't beat it.