laptop cooler pad actually not that useful. they usually only help bring down the temperature by 1 to 2 degrees at most. doesn't help much with regards of the laptop's performance.
i also using one from cooler master, kind of expensive though but i still brought it cos those free/cheap/unknown brand coolers their fan not as strong as the cooler master one.
if you want to buy one cannot anyhow buy. you must know when the air intake vent on your laptop is and buy a cooler pad that blows cool air directly into the vent.
i remember last time got some laptop their intake vent is at the side of the laptop so laptop coolers are pointless for those designs.