Hmm. A late 1970s linear. Kinda like asking if a 1977 car is "a good one".
Mighta been four-plus decades ago. But this many years down the line what matters more is the mileage, and how hard those miles were.
If it has been treated well, and all the suicidal-age electrolytic caps are updated, should serve you well. If those caps are original, they will fail. Can't predict exactly when, but the pattern we see is pretty soon after you put it back in harness. And if the box is genuine unused "NOS" you might get a few months.
If some previous owner was hard on it, there will be other wear issues.
And if that 1977 car has original radiator hoses, don't set out on a road trip before they get changed. Might get stranded.
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