For ARC lovers, Problems?

I haven't had reliability issues with ARC equipment even after many decades of ownership. It sounds like you purchased your ARC gear used, so perhaps that's part of the problem.

For a great sounding and reliable tube preamp try listening to Nagra Classic or Luxman (CL-38 or CL-1000)

https://www.nagraaudio.com/product/classic-preamp/

I used to own Audio Research and now own Luxman

I have owned ARC gear for over 30 years and have not had any reliability issues. Some years ago I had a 6550 go that took out a resistor, but that is about it. I have had absolutely no problems with my Ref 5se going through tubes. My Ref 2se either. The Ref 10 was probably just a fluke. Maybe a poor batch of tubes or something. Was the Ref 10 sent in for service to the ARC factory? They are usually very thorough.

 I have had other gear in my system from time to time but always went back to ARC. There is just nothing that compares to the sound of their preamps.  I would go for the Ref 6se if you can. Long term I doubt you will be satisfied with something else.

Get VAC better sound better made better company.

I have been using ARC products for over 30 years and had almost no problems, and great service the one time I had to return a piece for repair (which was due to an error on my part).