Just recently purchased a 7.3FX. Size 17.5.
I was actually intent on buying the 7.2 but after testing the 7.3 and the Giant Escape 2, I changed my mind. I'm just a casual cyclist and I don't know much about bicycles but both felt much better than the 7.2. In the end it was a close call but I went with the 7.3.
I'm amazed at how light weight this bicycle is. In comparison, my old Panasonic Sport 500 weighs a ton!
Added a red&white sticker next to the white Trek lettering just to make mine easier to find when stacked next to similar Trek or black bicycles.