One important aspect to take in consideration for have an idea about the quality of LED lamps is the POWER FACTOR
Power factor explanation is really complex because in an AC electrical power system it is defined as the ratio between the real power and the apparent power in the circuit.
In simply put, Power Factor means how much power is using by LED lamps. It is measured on a scale of 0 to 1.
In case of PF = 1, the electrical system works with an efficiency of 100% all energy supplied to the bulb is fully used.
How much more PF is far than 1, more energy is wasted usually as heat causing a faster lamps degradation and reducing the lamps life.