Do not Buy Cheap Rims Or Wheels From Ebay Aliexpress DHgate or other website.
You will ask why ebay ,aliexpress,dhgate or other chinese company sell carbon rims and wheels very cheaper?
Following is the answer：
1）you must know ebay ,aliexpress,dhgate need 15% fee ,the accurate products price need reduce 15%.so the products price is low than show on website.
2）factory can produce 100% qualified product, have 2-5 pcs bad rims when produce 100pcs. factory will sell the bad rims to some trade company in very low price !
3）some factories produce carbon rims use bad carbon fiber, like chinsese carbon fiber ,or carbon fiber incl glassy fiber,it can save more cost.
4）Use simple production process to save the costly, it will let carbon rims not stable.
All rim is round, and have carbon finish,so you say all rims is the same.
1 ) if you are buy for yourself use, i suggest you buy from your local agents.
2) If you are buy for sell, i suggest you test sample first .
Why CarbonBikeKits (CBK Sports) have good carbon rims you can look this url http://demo.carbonbikekits.com/product/