Re: Are the knockoffs any good?
Just like the last two posters, I think it's better for you to get the cheaper Nikes/Adidas shoes. They might be cheap, but they are worth it. May I suggest looking for a cheap pair of Adidas TS Lightspeeds? They super comfy and pretty light. Got them around 4 years ago and they still work magic (if you're wondering why it still fits after 4 years, I have to buy bigger shoes because I'm falt-footed and need arch support which adds around an inch of thickness to my foot).
As for knockoffs, well, I guess they work okay. I used to have a pair of fake T-Mac 5's, the one that supposedly had a piece of hardwood on the back of the shoe or something. It worked pretty well, but after a few months my feet grew so I got some Decade GCS'. The T-Mac's were good enough for the price, but yeah, I'd still suggest getting the more economical, old (but still good) sneakers.