Challenge Hi Fi Solid State Receiver Mark IIIB 1981 - Mint Condition

It is rare to offer a piece of audio equipment some 44 years old in mint condition but that is what we have here. It was purchased through an auction house over 10 years ago as "New Old Stock" and has remained boxed and unused since.
It may have originally been purchased by a private individual as a person's name has been hand written on the box, but it is perfectly believable that it has never been in regularly use...it is immaculate.
This is an "in-house" brand / model commissioned and sold by local Adelaide retailer Challenge HiFi, who are still a dominant local retailer through to current day.
It is essentially a copy of the Project/One Mark lllB originally commissioned by an American Company running a chain of stores trading under the name Playback Audio. Challenge HiFi were obviously offered the chance to piggy-back on this initiative for the Australian market.
In Europe the same product was branded as a Deviton 4060.
At first glance it appears that the product is a variation on a Pioneer SX-750. Many have said this to be the case, but the internal assembly of the Mark lllB suggests otherwise.
A reviewer covering the release of a more powerful Project/One Mark IV B model at the time summarised the situation in this way:
"The front panel of the Project/One Mark lV B stereo AM/FM receiver suggests that Playback Inc, was not quite ready to tread new design grounds but rather "borrowed" the best features and layout from several of the better known receivers around".
In the case of the Mark lllB, its specifications run very close but not quite identical to the Pioneer SX-750, producing a continuous 50 watts per channel into 8 ohms, among other things. And there are some welcome differences, such as a finely crafted teak veneer case (not a wood-grain vinyl wrap), and a separate power switch instead of the combined power / speaker selection switch on the SX-750, which can cause problems. Plus the Mark lllB has a midrange tone control in addition to the treble and bass control.
The SX-750 also has an awkward horizontal ledge on the back for RCA jacks and the like, which is not present on the Mark lllB. These were selling points that could potentially favour the in-house brand over the likes of the Pioneer SX-750.
We have had this unit checked over professionally and very little was needed to get it into good working order. Surprisingly, the original capacitors were still in good condition. About all that was needed was some contact cleaning of the volume pot to get things right again. The technician working on it was quite impressed with the overall quality of the internal build. In the style of other quality Japanese receivers of that era, the sound produced is rich and warm, very nice indeed!
This unit presents to the quality of "New Old Stock". All we've found is a tiny flyspeck on the back of the perspex window of the tuning dial near the number 96, but that's about it (see photo).
So, if you'd like a piece of vintage gear that looks great, sounds great, and can treasured as something of a collectible, this could be the one for you.
An in-store audition before purchase is welcome.