Conclusion: This item does not noticeably cool my laptop. I returned the item to the store.
OS: Windows 7 Home Premium, 64 bit
Laptop: ASUS K52F
I checked core temperatures with Core Temp and disc temperature with Acronis Drive Monitor.
I ran the following malware scanning programs simultaneously on the laptop for 45 minutes in order to exercise the CPU & disc, and cause the laptop to heat.
After 45 minutes I recorded core and disc temperatures.
I then placed the laptop on top of the cooling pad and plugged in the USB cable to start the fan. I ran the unit for 30 minutes and checked the temperatures again.
I noticed no change in core temperatures. The disc temperature had increased.
Observation: The position of the laptop on cooling pad is such that there is little room for warm air to be dissipated by the fan. Frankly I do not see how this unit could ever cool a laptop.
I am probably better off buying the appropriate can of compressed air and cleaning the laptop.