I have found over the years that with power tools, specifically air tools, the question of quality depends on the use. If you plan on making a living with them, they will likely not last long. If you are only going to use them occasionally, at home, they may do alright if you maintain them with oil. The impact probably won't have as mush power as one of the name brands, although they all varry anyway.
Basically.... it is all in what you expect them to do. A good high power impact can cost you $200+. Same for the air ratchet. The sockets most likely are not the highest quality, and may not fit as good as name brands, but may be alright for what you want them to do. Then again, you do get alot of little stuff and a nice case for it all.