My TRT800 works excellent.... In a permit aircraft so no CAA issues.
Service from LX avionics is absolutely fantastic.
Mate had a problem with his when a poor install saw the co-axial being departed from the antenna and got running high SWR and popped the output side of the transmitter. LX directed him to send it to Germany, 7 days later and a small bill for 48 euro and all was back in situ and working fine.
Good experience here, and works fine. Also, its small profile is excellent and is one of the very few units with the encoder built into the actual transponder itself.
Jon