I chose to buy the one that I bought. Certainly didn't "need" to, I wanted to. I like to buy good quality parts for my car as I take a lot of pride in my vehicles. As I mentioned to you earlier in this thread, literally ANY intercooler would be an improvement over the stock item - that includes any Chinese ebay jobbies as well.
As proven by this guy doing the testing, not all intercoolers are the same. No doubt the chinese Wanger will be an improvement over stock, but you are kidding yourself if you think it will perform as well as the big name brands using high quality cores and end tanks. Does it matter in the real world - probably not. Will there be any performance advantage in the real world - probably not.
You like to buy chinese parts (tyres/intake/intercooler etc) which I do not agree with - but that's your choice.
By the way, if you looked on this guys blog you would find some of the answers you want:
Mk7 GTI/R Intercooler Comparison | My Golf Mk7 GTI
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