I just ordered the Linear EX slim in Slate this morning directly from Spigen lol
From browsing online there is a thread ins the XDA forums about people ordering from DX-Box and never getting an update on their orders so I wouldn't really take the risk to save ~10 dollars. Plus they could also be counterfeit which is probably a good bet at this point and not fit correctly. I think even legit Spigen stuff goes for near retail on Ebay.
I bought a cheap bumper where the volume buttons don't line up and said hell with it.