ST/R $1978/pr factory assem., about $1350/pr kit.
QSO 404 about $378/pr fact. assem., early finish during era of the ST/R was real wood veneer, later finish was vinyl.
IF fact. assem. (the XO is very complex for DIY and is likely incorrect unless assembled by an expert or extremely patient hobbyist who triple checked every connection, it looks like a huge octopus), IF all in original proper working order (gravity has taken its toll on the PRs, vertical drivers should be rotated 180-degrees every few years) and IF within driving distance you could do a LOT WORSE for $750/set of five. Proper functioning ST/R move huge quantities of low-20Hz air. Because of the post implying the image may be very dated, I'd do nothing without an image including the speakers and a newspaper with current date.
ST/R in real walnut veneer looked awesome IMO. A somewhat longer than average listening distance required for smoothest driver integration. Then all systems go at just about any playback level (with enough power/current). The top firing piezo works.
Back to the XO: a kit buyer called the Plant one day many years after purchase, requesting a copy of the lost assembly instructions. He said the empty enclosures were currently serving well as humongous cat condos.
