Now do the math at 20k miles, and it's 400 gallon difference. Which is a realistic number for annual driving. So roughly $1,500 worth of gas (not even counting time wasted on trips to fill up, etc.) times an expected use of 8-10 years, and you're looking at about 15k in savings. Which is significant. Plus a smaller strain on resources, good for the ole planet and such.
And while with small numbers you can make a case that there is a larger difference from 15 to 25 (though it's still just a 67% increase vs a 100% increase) the numbers are still much better with 50mpg than 15mpg. Going from 15 to 25 will save you roughly 533 gallons per year, but going from 15 to 50 will save you 933 gallons per year.
Over the life of the car, say 150,000 miles, you would buy 10,000 gallons at 15mpg, 6,000 at 25mpg, and 3,000 at 50mpg, so there is still a very good case for better gas mileage. You're still doubling your effective rate going from 25 to 50.
Plus, I just know it's nice only filling my tank once every 3 weeks or so. I went from 20 to about 35, and it's great. Plus my car is still plenty quick, but I haven't jumped to a hybrid yet.
And while with small numbers you can make a case that there is a larger difference from 15 to 25 (though it's still just a 67% increase vs a 100% increase) the numbers are still much better with 50mpg than 15mpg. Going from 15 to 25 will save you roughly 533 gallons per year, but going from 15 to 50 will save you 933 gallons per year.
Over the life of the car, say 150,000 miles, you would buy 10,000 gallons at 15mpg, 6,000 at 25mpg, and 3,000 at 50mpg, so there is still a very good case for better gas mileage. You're still doubling your effective rate going from 25 to 50.
Plus, I just know it's nice only filling my tank once every 3 weeks or so. I went from 20 to about 35, and it's great. Plus my car is still plenty quick, but I haven't jumped to a hybrid yet.