Is buying a vintage Marantz 1150 Integrated Amp a good idea?

I'm considering replacing a fine but mediocre-sounding Rotel 930AX integrated amplifier with a vintage Marantz Model 1150 from the 1970s but I have a lot of considerations.

Although it has 75 watts per channel as opposed to the 30 watts from the Rotel and most likely would sound much better, being that it is so old (but in very good condition) and the parts may be very expensive if repairs are needed or it may fail all together, would you play it safe or go for it?

My plan is to trade in the Rotel for it so I would not have any backup if the thing dies.

Many people think they are thinking when they are merely rearranging their prejudices WJ