I apologize if this has been discussed, but hopefully I can add some insight. I'm looking at buying a touring bike, and I've been investigating all the usual suspects in the price range (Fuji Touring, Jamis Aurora, Trek 520, Cannondale T800, Bianchi Volpe). I keep hearing how most touring bikes don't have low enough gearing, so I thought I'd investigate. Let's take two examples. The Cannondale T800 seems to have the lowest gearing, with a ratio of 26 in the front to 34 in the back. The Jamis Aurora has a ratio of 30/32. Now, this is the calculation for speed:

Speed = Gear Ratio * Cadence [rpm] * Wheel Circumference [in] * Conversion of inches/min to mph

Assuming a cadence of 80 (I'm a beginner, not sure what my cadence is but it's probably not the oft quoted 90) this gives bottom speeds of 4.8 mph for the Cannondale and 5.9 mph for the Jamis. Now, I know this is for the case when climbing a hill with a load, but does the 1 mph make that much of a difference? I have panniers on my hybrid bike now and when climbing a hill I can't travel in a straight line going that slow (I'm sure the longer wheel base of a touring bike would help though). Is this an overstated problem? Does it really not matter that much as long as the ratios are within about 20% of each other? Any input would be appreciated.

By the way, I know that I can ask them to swap out the crankset when buying the bike, I'm trying to minimize costs. Also, sorry if some of my terminology is wrong, I'm still learning.