I also like the PSX-ACs, they have both over voltage and over current protection and have worked well for me here. I bought these before I decided on my main power supplies (PH-180s), so I now have PSX-ACs supplied from PH-180s feeding my TIU inputs for maximum overkill. Like Cappilot, I am using most of the PSX-ACs additional options.
My current set up was completed a little over 5 years ago and I haven't lost a TIU channel or any engine electronics and I'm happy with the overkill. I'm using a Rev L TIU, and both DCS and Legacy systems. No problems other than from operator (usually me) error. All my MTH engines are PS3, Lionel engines are Legacy and all are diesels, FWIW.