This unit is the one to get! I purchased the Radio-Tone unit from the Hong Kong vendor on eBay. It "worked" - but had one major issue and two shortcomings. First, the voice quality was very poor. I don't know if it was the sampling rate or the quantization level, but it is poor, in my opinion. The first shortcoming was that the unit sometimes triggered my Relm MPV32 radio into cycling into an endless transmit loop - there is no way to customize the settings. The second shortcoming continues with the options - there are very few configurable menu items. In short - it works, but it's not reliable or flexible.
So I decided to try the ADS-SR1, and right out of the box it worked. I was able to customize the incoming audio signal levels from the radio interface, and the recorded audio sounds GREAT! Certainly as good as 3.5KHz of audio bandwidth is going to take. Second, the device is very flexible in programming options. I won't use many at all, but the key ones to customize the squelch tail sounds and prevent cycling with the transmitter are key. In fact, I barely had to tune them - they came factory set at very usable values.
Well done. Well built.Rating: [5 of 5 Stars!]