My usual is to drive at least three days to/from work before looking to fill up. (Work is ~~47 miles one way.) Last week I tried it a fourth day, the "gas light" came on before I got to the staion, and I got a little worried, but I made it. I got about 370 miles, put in 20.7gallons. (I fill up the neck. I won' stop filling until there is gas to the cap.) Still stinky mileage, but you do have range.
By the way, I'm all stock. Didn't run the air beyond defrost.
LOVE THE "V".
D.W.
#0147
Just a FYI about overfilling up to the neck...
It's possible to damage the EVAP cannister/ system by doing so... a little searching will provide more info to back this up.