I've heard that it is not very good, on several occasions, in one instance I've seen it installed (incorrectly and without common sense involved though) and it was very poor. There is a reason it's the cheapest kit on the market I think. There are alot of parts not included in that kit, that you would need to make this work well.
Stage two has everything that I need and why is it that bad? Does it break down or it doesnot give you enough power for the money. O je, by the way they are going to sell me head package and stage II turbo kit(bouth together) for 4000 and no shiping and no tax fees.