 How can you decide on which vehicle is best for you? Is Miles Per Gallon a good way to compare vehicles?

Maybe. Looking at Miles Per Gallon will give you an indication of how efficient a vehicle is. There is one downside, however. When you compare a car that gets 35MPG vs one that gets 48MPG there seems to be a lot of difference. But if you take the number of gallons used in a typical year at each of those ratings, you'll see that the difference isn't as much as the numbers indicate. Running at 35MPG at about 15,000 miles per year, you would burn through 428 gallons of fuel. At 38MPG, you would burn 394. That difference at \$4 per gallon is \$136 per year.

It would be better to rate the consumption of gas over a typical 15,000 year. I've taken the base models of each of these vehicles with base engines, and manual trannys where available. I'm assuming 15,000 miles per year, and I averaged the EPA city/highway rating together. The dollar amount is based on \$4 per gallon, which we seem to be near right now.

2008 Chevy Tahoe (base) 16.5mpg=909 gallons = \$3636
2008 Chevy Tahoe hybrid 21.5mpg=697 gallons = \$2788

2008 Honda Civic 30mpg = 500 gallons per year = \$2000
2008 Honda Civic Hybrid 42mpg = 357 gallons = \$1428
2008 Toyota Corolla 31mpg = 483 gallons = \$1932
2008 Toyota Prius Hybrid 46mpg = 326 gallons = \$1304

This data shows us that the Tahoe increases by 5mpg, but saves a whopping \$900 per year. In comparison, the Honda Civic increases by 12MPG, but saves only \$572 per year.

Here's a handy dandy chart showing how much fuel costs at \$4 and 15,000 per year:

20mpg = 750 gal = \$3000
22mpg = 681 gal = \$2727
24mpg = 625 gal = \$2500
26mpg = 577 gal = \$2307
28mpg = 535 gal = \$2142
30mpg = 500 gal = \$2000
32mpg = 468 gal = \$1875
34mpg = 441 gal = \$1764
36mpg = 417 gal = \$1667
38mpg = 395 gal = \$1578
40mpg = 375 gal = \$1500
42mpg = 341 gal = \$1428
44mpg = 340 gal = \$1363
46mpg = 326 gal = \$1304
48mpg = 312 gal = \$1250
50mpg = 300 gal = \$1200