I've owned a SP9MkIII pre-amp for 13 years, from new, and the only problem was a rocker switch which failed, needing replacement. Used a variety of 6922s without issues, currently NOS Mullard.
Regarding power amps, had a D70 for a year, and then a D125 for 8 years(both second hand) - in both cases they developed faults which the local (Sydney, Australia)technicians could not fix, despite repeated costly attempts. Loved the sound, especially of the D125, but ownership was frustrating - for the last two years the D125 pretty much sat unused, and old Luxman SS amp filled the gap.
I'm afraid I wouldn't buy another ARC power amp.
Regarding power amps, had a D70 for a year, and then a D125 for 8 years(both second hand) - in both cases they developed faults which the local (Sydney, Australia)technicians could not fix, despite repeated costly attempts. Loved the sound, especially of the D125, but ownership was frustrating - for the last two years the D125 pretty much sat unused, and old Luxman SS amp filled the gap.
I'm afraid I wouldn't buy another ARC power amp.