I just got my diffuser that I ordered from eBay. Actually ended up messaging the guy and we went directly through PayPal (skipped eBay) and he gave it to me $299 shipped. I was a little concerned because the eBay page showed that it would ship from California, but when I got the tracking number it actually shipped from Taiwan. I contacted them to ask about it, he said that they only had 1 left in California and it had some defects, so they shipped it straight from their factory. They shipped via DHL Express, so it only took a few days to get delivered.
Vehicle: M4
Part: M Performance Style Carbon Diffuser
Brand: Replica
Link, eBay seller, item number:
LINK
Fitment 1-10(best), reason for score: 9 (holes didn't match up perfectly)
Quality 1-10(best), reason for score: 9 (not 100% carbon fiber)
Item price: $299
Shipping price: $0
Item location: California/Taiwan
I'll post some pictures today or tomorrow (just remembered that I took them on my wifes phone since mine ran out of juice). Overall I'm very satisfied with it. I was worried that it shipped from Taiwan in case something was damaged, but it was packaged well. It isn't all carbon fiber though, seems almost like carbon fiber wrapped around fiberglass. Not nearly as light as the real carbon fiber spoiler I have. But once installed it looks excellent! Fitment is almost 100%. Weave looks great as well. When examining close up before install, you can see it's not perfect, but once installed it's nearly impossible to tell. The bottom middle clips that are screwed in didn't match up perfectly to the factory holes, but I just had to screw one in, then push the middle of the diffuser to bend it a bit until it lined up.
Would highly recommend this to someone looking for a budget diffuser.