I'll probably get hated on but while I was reading up on other turbos these popped up. http://xs-power.com/audi-turbokits-5.htm
I saw the price of 644 shipped. Wtf. From what I have heard is that these are generic ko4s but the ports are a little smaller. Any info on these. Anyone ever dared to run them?

IMHO its a crap! Some chinese turbos have 19 mm port, some 14 mm (like the turbos I bought), ori turbos 24 mm. So 14mm turbos overboost all the time.

"Due to the nature of the use of these products, no warranty is implied or given."

They probably mean that since you'll likely use these on a vehicle, and not as paperweights, there is no warranty.

Strong backing for the stuff they sell.

I had two that went bad k04-15 off ebay but in my experience they went bad because the metal section where the wastegate flap arm goes through on the turbine houseing ends up getting loose and making the flap off center and allows boost to leak. I have since repaired three of these by tig welding the collar to the housing but not after porting the wastegate hole to decrease creep.
They are hit or miss but they do last if they are getting proper oil. Even while pushing 20psi it still has good seals and no shaft play. Just put one that I fixed in wifes car and got one left stored away.