This product is almost like a life vest for your guitar strings. It really helps fight against the coercion and string degradation that occurs naturally over time as you play your guitar and as it sits in its case while travelling or at home or whatever. It saves you the stress of having to change your dead strings quite as often, which is great, cause everyone hates changing strings!
The fast fret also helps with playing speed, but to be honest I prefer to use it as a cleaner to preserve my strings and clean my fret board, rather than a way for the guitar to play faster, because it tends to make my hand feel very greasy, even after leaving it to dry for a few hours. So I just apply it on the guitar and leave it over night to protect the strings. Works well for me.