Before I purchase my 2001 Echo , in June of 2000, I researched all I could. Consumer reports showed that long term road tests in cold weather regions proved to shave off about 4 to 8 mpg off the estimated.
I remember driving my echo home from the dealer just over 250 miles on a 1/4 tank. I still average around 32/34 mpg, even after 198,000 miles. I have been very happy!
When I took the baby stroller out of the truck and the car seat out my milage went back up to around 36/38, Amazing what a difference that makes.