I worked briefly in a bak kwa shop before.
The owner (now deceased) told me that according to the
history of bak kwa business in chinkapore, the 1st to start
was "Lau Hock Guan" followed in 2nd by "Kim Hock Guan"
The 3rd company to start was Hock Chee Guan
Bee Chung Hiang came much later.
In earlier times (1960s) slicing of raw bak kwa meat must be done
manually by a very expierienced senior employee with many years of
apprentice.
At that time they not only used pork but also beef meat coated with
spicy hot chillies. Not sure what is happening now.
Eating bak kwa nowdays is just like eating gold. "Bery
X-pensive"