Great comments!The early Marantz receivers, and even the first few ranges out of the SRC (Standard Radio Corporation) factory in Japan are seriously over-valued and honestly not that good. I'd take an early, unmolested Sony receiver over a Marantz, apart from the looks, which have become so classic and desirable.
The pick of the early 1970s Marantz is the 2275 IMO, but things really improved when I believe there was a shift in the manufacturer for a period. I am convinced that the twin 1978 range came out of both SRC and Matsushita, something that nobody talks about. The range that included the 2218/26B/38B/52B was SRC and I believe the 1515/1530/1550 (model MR250/255 in the US) was Matsushita.
My pick if you want a Marantz receiver, with excellent performance, better reliability and not paying through the nose, is the 1550.
I could go into all the whys and comparisons, but then the 'internet' will 'discover' it as a sleeper and the bargains will disappear.
I have one of these tuner preamps (apart for rebuild currently)
Sony STC-7000 on thevintageknob.org
vintage Sony's only pre-ceiver : an ST-5130 with a preamp section added, MOS-FET charged !
www.thevintageknob.org
And one of these (the home market version for Japan, smooth knobs, F badge, walnut case):
Sony TA-2000F on thevintageknob.org
vintage Sony high-end 1971 pre-amplifier from the 2nd Sony ES series !
www.thevintageknob.org
I'll probably offer that one up for sale soon anyway.
I had several of the mid range marantz's - none of them lasted more than a few years; all failed eventually, so I stuck w/Sony pre's.