There is great variance among the various Chinese sites. Some of them look awful, and some of them look pretty close to the real thing. I have a couple of knock-offs that I could probably fool the average fan into thinking they are authentic.
However, I much prefer to go the authentic route myself when I can find the right price (which is a challenge.....you have to be on eBay at the right time, or catch a great online sale, etc.). I got a Marino jersey for $100 a couple of years after he retired (got it customized off starstruck.com).....found a barely used Ricky jersey on eBay last year for about $75.....and shortly before the ring of honor ceremony this year I snagged a JT jersey, brand new with tags, for $50, also on eBay. Still can't believe my luck on that one.
even on ebay . there are a lot of knockoffs there . have you got any pics about your cutsom jersey . i'm interested in see that