......These things are complete rubbish..........
Below is a direct cut and paste of my $0.02 worth last time exactly same question was asked elsewhere on more than one occasion!
It is indeed 'too good to be true.' Avoid even at the paltry cost of said item would be my advice! A direct cut and paste post of mine of a thread on another forum on the subject matter and the reasoning behind my inherent hate for these cheap items. Go get a proper tune regardless of the fact it is much more expensive! Engines are modulated, they have safety margins built in so that they can operate in the cold of Alaska/Canada or the heat of Saudi Arabia without any adjustments. A remap will safely take into account your region and climate and then eat into these safety margins to get the best out of your engine whilst still maintaining adequate safety margins. These plug and play boxes often don't give a toss about safety margins but just throw more fuel at the engine.
As an Electrical Engineer and having some experience in the tuning World of 4x4 vehicles there are several ways of 'fooling' the ECU to throw more fuel at the engine across the entire range. There are many drawbacks. The crudest version is simply a resistor to lower the fuel pressure signal to the ECU, so the ECU raises it by means of compensating as it doesn't match its set point. Higher fuel pressure demand means more fuel injected per firing, but it takes NO account of the other engine parameters required to determine if this is a good idea or not.
These parameters can include but are not limited to fuel temperature, boost pressure if turbo'd or supercharged, engine temperature, inlet air temperature, charge temperature, air flow, gearbox gear and so forth,
A remap does increase fuelling, but by altering the maps which are read as a result of looking at all these other parameters FIRST. A simple plug in tuning box lets the ECU work out where it should be operating, and then just bungs some on top, and lies in return.
These simple solutions are best avoided at all costs IMHO. Also what you are getting for your money if you have the acumen can be sourced and put together for less than $10-$15 in most cases.
LATER EDIT Did a bit of research and is as expected. Cut and paste from Booster Plug, spelling errors and grammatical errors included....
If you trick the Fuel Injection ECU to think the ambient air temperature is lower than the actual readings, the ECU will richen up the injected mixture by a certain amount.
The correct enrichment will be a huge improvement to the driveability of your bike.