I lived in '香港仔' center, 德仔 used to use a very complicated and expensive AYK charger to charge those 1200mah batteries.
周應生 also run his AYK Bobcat there, 德仔 ran a modified Tamiya Fox, all converted to on-road setting. Those cars were very fast.
That was the summer of 1985. After that I spent too much time studying and never really pay attention to '飛翔模型', or any 模型 for a long time. Also no $$ to play la, have to sell off my stuffs and move on with live.... In no time I found '飛翔模型' closed down.... but I did not miss them too much