Vintage gear does not "need repair constantly ". In fact it is probably better made than most modern units. As long as any electrolytic caps are replaced you should be good to go.
Which pre should I choose?
There are two Pre in our 2nd hand market. One is Accuphase C-290 (selling at: US$3300) which start to produce in 1993. The other is Accuphase C-275V (selling at: US$2600) which start to produce in 2000. My power is Accuphase CA-47 to drive Dynaudio Countour 1.3SE. I like warm & thick & not to fast sound. Do you have good ideas? I prefer to listen to classical music mostly.