Cheap and easy to build and use

Constant current and constant voltage adjustment [CC, CV] capability

1.2V to 25V and 25mA to 3A controlling range

Easy to adjust the parameters (optimum use of variable resistors to control the voltage and current) 

The design follows the EMC rules

It is easy to mount a heatsink on the LM2576

It uses a real shunt resistor (not a PCB track) to sense the current