Not just in Johor, but practically anywhere in Malaysia, are
better than those sold by the local vendors. The burger patties
used are the same, from the very same factory in Malaysia. The
difference lies in the way they cook the patties. The Malaysian
vendors, from what I observe, took great details in cooking the
patties. From slicing the patties into half to adding the extra
spices and everything else.
Rather than buy from those pasar malam, I'd prefer buying the
10-piece patty pack and cook it myself at home.
My 2 cents, though.