There were a couple of snags.
Basically what they did was overestimate the county taxes and registration fees and included that in my financing (I had cash but they wouldn't accept checks or cashier's checks out of state). They gave me a temporary Oregon registration that was good for about a month while I got tags down here.
I had to go to the DMV twice, because I didn't know I needed a smog the first time.
And the TTL overestimation? It ended up being about $350. The DMV wouldn't give me the check directly, they sent it back to the dealer. The dealer sent it to Bank of America (the financier). Since I had paid the loan off immediately, BoA sent it back to the dealer. The dealer finally mailed it back down to me (whew!).
Kind of a pain in the butt, but worth saving the money. And the drive back home through Modoc and the Sierras was beautiful.