Any Audio Research Reference 610T Owners here?

Thank you all for your input! ARC does in fact have tubes for my 610T amps but they are most of the way to $4K for a complete set. ARC advises that their tubes are much more closely matched than available at retail. I understand there would be difficulty in getting four matched octets of 6550 and then matching the other half dozen tubes that run them to ARC specs. What do you folks think? Could I get almost as good results from a good retailer? The prices I'm seeing are a little more than a third the cost of ARC at retail.

Re-tubing cost is the BIGGEST drawback of the ARC 610T. Close second, heat, weight and power consumption.

you should also beware of the fact ,listen to the audio for an hour before you would left the house , you will NOT power up a poweramp like the 610T . That's why I bought
a SS poweramp .I 'm sure I 'm not the only one , my audiofriend replaced a beautiful sounding REF 300 by the Boulder ( also not bad sounding ) , for the reason I mentioned.

Great amp in the winter plenty of heat in the summer wear a bathing suit.

I email to ARC, he reply and said that KT120 cannot be use on original 6550C unless upgraded power supply. I just bought a mint ARC601T with only 122hrs in it, i have a Hansen Emperor 6ohms, which connection to the amp ohms i should use?
I replaced Krell FPB600.