Maybe it still has a headliner that doesn't look more at home in a 1998 Chevy.
I picked it up today. Even though the VIN was lower than the one I was originally given (JF0013XX vs. JF0038XX), it only had 10 miles on it. The headliner looks OK to me (although it isn't Alcantara and I'm not sure what it should look like). The car was in great condition (better than my Model X VIN 18XX when I picked it up) and looks great! They had the red Model 3 display model out there in the lobby area of the new Delivery Center in Fremont (on Fremont Blvd. about one mile south of the factory), and in the huge pick-up area they had about 8 Model 3s (white, black, blue, red, and midnight silver)!
My initial impressions are quite favorable: it feels lighter and more nimble than the Model X (which I'm quite familiar with) and Model S (which I've driven quite a bit as loaner vehicles while the early X has been serviced)...it reminds me a bit of my 2004 BMW 3 series as far as feel and acceleration go (it was a 4-door ZHP performance model). Acceleration is quite good, but not quite as crazy as a Model S. The head- and legroom are very good (it even has more headroom than the S, in my opinion), which is critical for me since I'm 6'8". I should also point out that the vision out the front is a bit better than an S because the front window seems to extend a bit higher (again, very helpful for tall people...I used to have to lean forward quite a bit in the S in order to see a high traffic signal when I was first in line). After only about 10 miles of driving (across the Dumbarton Bridge to the peninsula to go back to work after picking it up during a long lunch break) I'm fairly confident I'll be happy to keep this car for awhile!
OK, I'll dig a bit for some criticisms... The interface is a bit different, but seemed natural (but there's no doubt it is a bit more cumbersome to use a touchscreen for almost everything, including adjusting the side mirrors, which will probably be almost impossible while driving). The doors seemed a bit difficult to close, but maybe that is due to it being new? The finish was great. The stereo seemed quite good (but not significantly better than the factory-upgraded stereo in my Model X). I have a feeling the glossy black plastic trim pieces in the center console are going to drive me a bit crazy with fingerprints, but when I mentioned that to the delivery specialist he said he heard they are probably going to offer some type of upgrade (possibly wood, like the Model X?) for these pieces at some point in the Tesla store.