I found the Motorokr T505 very very useful. I have struggled with bluetooth headsets for many years. They didnt fit my ears well, the battery would be bothersome (I also had to use a special in-car charger), and there were times when even though I could hear well in the headset, the person on the other end could not hear me (again weak batteries would make that happen). This device is good because I dont have to fiddle with putting in my ears. The speakerphone is louder than my Blackberry, and the mic is quite sensitive. It stays attached to my visor in the car, and charges off of my regular USB type connector on the Blackberry charger. The device comes with its own car charger, but if you already have a car charger (USB tip), you can choose not to clutter your car with wires. The battery life in FM transmit mode is almost as good as they say. Stayed charged for me for days! The best feature is the FM transmission of the call. The frequency is set automatically, although this is something I wish I had a manual choice to control. There is no LCD display on the device (which would have been nice to see the frequency of the FM station its transmitting too).
I do a lot of my office conference calls using this thing -- folks on the other end cant figure out if I am using a bluetooth speakerphone. For them its like I am using my cellphone. If you sit in a parking lot while talking on this, folks on the other end sometimes think you are at home or in the office talking -- obviously since there is no noise from driving on the roads. Overall this is highly recommended. I am just not giving it 5 stars, because I would have wanted these features:
-- ability to choose the FM frequency
-- LCD display to remind me what the FM freq is.
-- continuous FM transmission (not just limited to 10 minutes or so when you are not in a call). You have to turn it on again after 10 minutes of no-use.

The MOTOROKR T505 was purchased by this reviewer to work with the Blackberry 8830 cellular phone for hands-free communication while in transit via automobile. Consideration to purchase a headset was not given much weight due to frequently-heard complaints that headsets are not very clear, the seeming social awkwardness of headsets, and the unnecessary need for hands-free communication by this reviewer unless driving a car. This Bluetooth device is extremely simple to use, and one can be assured that this is the case since this reviewer lost the instructions soon after receipt and was able to put it into use in less than 10 minutes. After using this device for over two months, this reviewer finds the MOTOROKR T505 to be fairly consistent in quality for both cellular phone calls as well as mp3 playback, both of which are transmitted via FM radio. While better hands-free devices of this genre might be available in the marketplace, no installation is required here because the MOTOROKR T505 works as a hub between phone and FM radio. And although FM radio is not technically needed, the user of this device may be disappointed by the limited available volume. Now, as good as this device might be, it has its quirks, and the potential purchaser needs to be aware of these. First of all, it is not possible to determine whether this device needs to be charged, although it does have a long battery life and this reviewer has never experienced it running out of power. Second, while this speaker initially assumed a heightened voice volume was necessary in order for cellular phone communication, both with the cellular phone itself and other individuals, after some trial-and-error this reviewer determined that a normal voice volume is all that is needed. The catch is that voice volume needs to be slightly raised if the device is not directly in front of the user. While these first two quirks are rather trivial, potential customers might want to pay a bit more attention to the third, which is solely due to MOTOROKR T505 usage of FM radio and will not be a factor if the FM radio option is not used. Over a time span of over two months, a 30-minute work commute in the western suburbs of Chicago, a rather populous area, necessitated a minimum of 4 changes between radio stations in order that optimal cellular phone call or mp3 playback clarity might be maintained. Slightly less than optimal clarity was typically maintained with about 2 changes between radio stations, and in the opinion of this reviewer such a factor should not sway anybody against use of this device, especially given the many positive qualities of this device. The device always recommends an FM radio station that offers the clearest communication, but it is unfortunate that the switching itself between FM radio stations is not hands-free. All in all, this device is recommended to those in pursuit of a relatively inexpensive solution for the automobile, but the potential customer just needs to be aware that this is not a perfect solution.

The Motorola T505 works great with my Treo 800w. The fact that it supports both phone calls and A2DP audio makes it a fantastic solution. I have been frustrated with the Treo 800w because of its low quality external speaker. When in a car you simply can't hear it. The Treo is great because of Sprint Navigation, Sprint TV, and the thousands of streaming options from the Kinoma Player software. But none of the these can be used in the car because you can't hear anything from the speaker. I have used a Jabra bluetooth headset that supports both voice and A2DP but even with that, I had to hold the earpiece tight to my ear when at freeway speeds.

The noise cancellation is really good. I placed some test voicemails to myself with the car windows down, the defroster at the highest setting, and the radio on. The quality of the call was very good. I could hear some slight popping once in awhile in the background but it was very minor and my voice remained strong and clear.

The T505's volume can be too loud, which is great. I can take and place calls, listen to Sprint Navigation instructions or listen to streaming music, all at comfortable volumes, all handsfree.

I am also pleasantly suprised by the FM transmitter. I have used a variety of FM transmitters in the past, including those in Garmin GPS units. I gave up on them because of the lack of signal quality. I am sure that this transmitter isn't more powerful than FCC guidelines but it seems like it. When activated the selected station is simply silent on my radio - no noise at all. And the auto frequency selector with voice instructions is a great feature of the T505.

For the ultimate test I have Orb installed on my home laptop. It is connected via 802.11g to my router. Using Kinoma Player on my Treo, I connected using Sprint 3G data to Orb on my laptop and streamed a song. My Treo connected to the T505 via bluetooth which then connected to my FM radio. The song played without drop-outs, without stuttering in a reasonable less-than-hifi quality. But remarkably decent for 4 different wireless links.

The T505 is a great product.

The iPod feture on an iPhone will not work. The iPhone will not transmit music via bluetooth. As a hands free device for the iPhone, that works great just do not expect to play your music.MOTOROKR T505 Bluetooth Car Kit

First of all I live in a rural area and commute to a town of about 200,000. Most frequencies the unit chooses have a signal in the back ground albeit not too strong a signal. I have had very good luck in my area getting a clear crisp voice coming out of the stereo in my truck.

It is easy to use and connects to my cell via Bluetooth easily. This thing works great. The fact that it can use any FM radio allows me to use my stereo system at home when working from my house. A boombox would work for a conf call while in the park...

I have not tried playing music from my cell phone via the Motorola unit, nor have I tried voice dialing.

The battery seems to last for a good amount of time. My commute is a couple of hours a day and I can go for a few days without recharging.

This is the best I have come across so far.