many people asked me about the v2.1 and v1.1 version esc difference, i will give a detailed information here.
they are same firmware, just the size difference, layer difference and weight difference.
v1.1 is one layer with larger pcb size, light in weight.
v2.1 is 2 layers with smaller pcb size but heavy in weight.
v1.1 need mount on the heat dissapation plate, v2.1 need mounted very well but need to air to cooling it down,