Just wanted to share my experience with the folks at repeaterid.com as they were a first class act start to finish!
I recently purchased a Retevis RT97S and was looking for an ID'er option and discovered the RepeaterID which had good but limited reviews. An initial email to the folks at repeaterid.com was promptly and thoroughly answered. I ended up purchasing the RepeaterID, Handydapter, & Passthrough Power Supply for my RT97S. Setup and installation were truly a simple plug & play that retained all original functions of the repeater without a rats nest of wiring/jumpers.
Once everything was verified as up & running I wanted to load a slightly longer ID audio file to the device to help with beaconing coverage of my new repeater. This file was actually a self-created stitch of two separate MP3 files that sounded great on my PC and phone, but had distorted audio when TX by the repeaterid through my repeater. Totally a 'me' problem (user error) that I couldn't figure out, so I hesitantly emailed repeaterid.com for advice. Jeff promptly answered my email and went above & beyond in troubleshooting the issue. Definitely top-tier customer service!
You'll have to decide of the RepeaterID is right for your application but in my case it was and I have had nothing but positive interactions and satisfaction with making this purchase.