[1] Born in Hong Kong, Choy received an education in England and was a graduate of Framlingham College.

[2] Choy, a player of slight build, was described as playing his tennis like a game of chess, using all angles to his tactical advantage.

At the 1938 Wimbledon Championships he troubled third seed Roderich Menzel in a second round match, losing 6–8 in the fifth set.

[3] In 1939 he played an All-Chinese final at the British Hard Court Championships, which he lost to Kho Sin-Kie.

[1][4] During World War II, Choy played in benefit matches to raise money for the China Relief Fund.