Reviews about an Ultrasound heater

Hello, new member but long time reader here. I am interested in starting PE and incorporating an US heating device as my tool to warm up and such.
I looked for a few , the indian brands seem to have a bad review in here so I ran away from them , the Current Solutions’ pro 2000 and the Soundcare are both too expensive for me (200$ and 800$) , and I don’t want to risk-invest a lot of money either.

But I did find a device that has a 3 MHz output , which is the GLOMEVE LW-007-A (for 70$ and less)

But I did not find any serious reviews about it

Does any member here own one ? Is it really 3 Mhz ? Is there any problem in the connecting surface (some users with other devices complain that the metal actually heat up)

Thanks for any replies !