JVC made some GREAT gear in the late 60's through early 80's before the black face equipment came along. For fun google JVC_graz if you want to see and drool over an amazing collection of JVC gear.
A lot of people poo-poo JVC and a lot of their stuff flies under the radar.
I wouldn't be surprised if those sound pretty good, especially four in each corner of a room.
Just my 2c.
If the price is good, I'd be very tempted to grab those. They look to be in very nice shape in the pic.
Glenn