I've owned the following:
(4) M-1.0T's, 2 of which I had fully upgraded to the MK2 opt 2.
(2) M-1.5T's that were also fully refurbed and upgraded.
(2) Silver 7T's
(2) TFM-45's
and a Lightstar 2.0.
Also, C19 and C6 pre amps.
They were all good sounding and powerful. As others mentioned, the 300 for the TFM55x is a good deal, you can buy and use then upgrade and not lose money. That's one key thing about Carver and Sunfire gear, You can play and trade w/o big losses. There's always a buyer ready for a clean example.
At their age though, be prepared to send in for refurb at some point. Of my pieces above, the 1.5's and the 7t's needed repair when I bought them. The others(minus the 2 built 1.0's) were original and still operated and sounded as they should when I sold them.