The gear range you get with that set up is 21 - 83 gear inches.. it is the same as what I run on my touring folder and although I'll spin out on hills and at speeds of 50kmh it works well for it's intended purpose and if you ran an 11-34 you's bump the top gear to around 90 gear inches.
Bike Friday's NWT comes with a 39/53 and an 11-x cassette for touring as you really don't need to exceed 100 gear inches unless you are racing.