Not recommended, poor product documentation, poor customer service and basic lack of courtesy.
I ordered BT-542-V2 and BT-PTT-ZU for my VX-5R
When the items arrived I followed the instructions to set them up on my radio but could not seem to get the PTT button to pair with the adapter. I got on a call with one of their techs and he walked me through everything several times, confirming each step and the results each time. It seemed to appear that the adapter was pairing with something but NOT the PTT, since the adapter went into PTT pairing mode for only a few seconds or so before exiting pairing mode. I tried pressing the PTT but nothing happened. We tried everything and I pointed out that the PTT paired fine with Zello on my phone so naturally by a process of elimination it would seem the adapter was faulty. They let me RMA the adapter (AT MY OWN COST) and when they received it they reported that it tested out OK in their lab. They sent me a replacement adapter but when it arrived it behaved the same way. I contacted the same tech again but this time he also asked me to check if my bluetooth audio device was connected and I said no and if that was required, it wasn’t stated as such in the instructions. He said that it was required in order for the PTT button to work. He never mentioned anything about this during the initial troubleshooting call and the instructions do not explicitly state this is actually necessary for the PTT button to function as expected. I responded by email to the same tech asking why he never asked me to check for a BT audio device during the initial troubleshooting and pointed out that during those sessions, the adapter probably WAS pairing with the PTT button but because no BT audio device was also connected to the adapter (and he never asked me about that) then the PTT function was not working. I also asked for a refund on my RMA shipping but to this day has just ignored my emails.