Hi I recently bought three Gamma units and the RF Meter. The units were incredibly easy to set up for Tx / Rx use and are very, very impressive in range. However I did experience some difficulties in using them for serial transmission, and the meter wasn't performing as expected. I contacted the help desk and I have to say the service and support I received is an absolute credit to the company. The meter needed a firmware upgrade and this was arranged (upon return worked perfectly) and my serial issues were quickly resolved by email. The Products have now all been put to good use in a "many-to-one" scenario and so far are working flawlessly. I am very happy to write this review and also to recommend R.F. Solutions. My only criticism would be the cost of courier, which seemed a little on the steep side. Perhaps alternatives could be offered?