Playcraft Railways was launched at the 1961 Toy Fair with the first sets being available by the following Christmas and it seems that Playcraft models were sold in Jouef boxes for a while.
Their main ploy was to sell through toyshops and department stores, in particular F W Woolworth Ltd., whose stores were low cost and widespread at the time. The advertisements of the time all stress the low cost of the models. They also drove home the idea of buying train sets rather than individual items and hence marketed a large number of sets considering the relatively small range of models they offered.
But by the middle of the 1960's the range had stagnated and no further British prototypes were made after 1964 and by about 1969, only models of French prototypes were being offered.
Perhaps the downfall of Playcraft was twofold. In the first place, apart from two locos, a number of coaches and a few wagons, they did not include enough British prototypes and the British models were poor compared to their continental stablemates. The idea of putting BR Type logos and other labels on continental stock didn't really fool anybody. Secondly they were basically to HO (3.5 mm to the foot) and not OO (4 mm to the foot) scale, which (unfortunately) was the preferred scale/gauge ratio in the UK.
The models including the Class 29 Bo-Bo survived the downfall of Playcraft and continued to be produced by Jouef well into the 1970's, but by then they were fitted with their own couplings.
Nowadays Playcraft Railways items can be picked up at swapmeets for very little but there are also some rarer items, such as the piggyback freight cars, the crane and some of the locomotives which are more expensive, but by no means in the same league as Hornby Dublo.
What's it worth? Take a look at this Playcraft price guide: sold listings for a value indication.