Have you ever owned a single speed? You could do 9 miles on a single speed easily. I have a 2004 Fuji Professional and a 2010 Kilo TT and for majority of my rides I take my Kilo. If it's a 40+ mile ride I'll usually take my Fuji, but I did an 80 on my Kilo last month.

Edit: I guess if you're riding with 2 gears you pretty much know what it would be like SS..