Tower Guy has made a good recommendation given your stated desire to receive the 'green' stations...
The antenna I referred to is similar but includes the capability to receive channels 2 through 6, which covers some of the stations at the bottom of the green and into the yellow. (ch 4 and possibly 3 though it is to the east so far as to be marginal with out a rotator)
If those channels do not have programing you are interested in, and the price is better, certainly go with one of the antennas TG has suggested.
Mileage values come out of the marketing department... The differences between these antennas is measured in a few decibels. You can often find technical details like 'gain' on solidsignals web site and also here
http://www.hdtvprimer.com/ANTENNAS/comparing.html So, no, don't be too concerned about "mileage".