The stepper drivers work just fine.
Arrived (U.S.A) 17 days after ordered (estimate was 20 - 38 days). The stepper driver set was well packed in a "BIGTREETECH" branded box. Several of the heat The heat-sinks were interlocked together (probably to minimize rattling i the box). This made it seem, at first glance, that too few heat sinks were present in the box. However the correct number of stepper drivers, heat-sinks, and wires with Dupont connectors were sent. A small simple card with pin-out information printed in color was also included.