I just bought the Rexton Trax a couple of days ago. I did compare the Bluetooth of the Kirkland S6/Resound and Rexton Trax 42/Siemens technology at Costco as part of my decision making process. The Rexton Trax is basically the same (per Rexton) as the Rexton Emerald, and almost the same as the Siemens Pure 7bx, as others have mentioned. The Siemens Easytek neck loop/pendant and the Rexton Connex Smart Connect neck loop / pendant appear identical in photographs.
My cell phone is an LG G3: one year old Android running the latest android operating system.
During my demo at Costco I tried the Kirklands with their clip-on phone mic device clipped to my collar. The Kirkland clip-on device allowed me to make a voice-dialed call from my Contacts with the phone still in my pocket. I believe I had to press a button on the device to begin and end the call process.
I was told that without wearing the Kirklands clip-on device I would still be able to hear the phone ring and the caller’s voice through my HAs, but I would still have to pull the phone out of my pocket and speak into the cell phone’s mic in order for them to hear me. I believe I also still had to press a button on the phone to answer and end the call if I wasn’t wearing the clip-on device and using its button.
I was told that the BT power output of the Kirkland HAs is greater (in order to reach the phone without the clip-on’s additional power supply) so this results in only a 3 day battery life of the HAs themselves.
The Rexton/Siemens neck loop device has its own rechargeable battery supply and amplifies the weaker BT signal (compared to the Kirklands signal output) of the Rexton/Siemens aids. This supposedly will approx triple the battery life of the HAs themselves compared to the Kirklands because the biggest power drain has been transferred to the pendant’s large battery. The Rexton neck loop’s pendant also has an imput jack for plugging in an external device like a music player. You must wear the neck loop device for Bluetooth transmissions to your HAs.
In making/receiving trial calls in the Costco Store, call reception through the HAs was similar for me with both Kirkland and Rextons, but my wife said the sound of my voice was clearer to her with the Rexton system.
The sound quality of BlueTooth streaming of music to the hearing aids from my phone was very tinny sounding with both Rexton and Kirkland, and there are discussions of possible causes and fixes in the Rexton Trax posts.
I eventually went with the Rexton Trax / Siemens system due to the voice quality noted by my wife, the much longer battery life, and what I perceived was better speech in noise comprehension as I walked around Costco comparing HAs.
The biggest downside compared to the Kirkland/resound system is that I do have to be wearing the neck loop to have the ringing of an incoming call transmitted to my HAs. But, I would have needed to wear the Kirkland clip-on device anyway for an actual hands-free call, so I felt I could live with that particular negative point. I also felt the neck loop would be almost impossible to lose compared to the Kirkland’s clip-on device, and the loop is not visible when worn under my shirt.