I did my first (and only tour for now) in 2013 on a converted hybrid machine (would be nice to find a lighter touring bike in the future). I went 3X7 and had a 48-38-28 with a 13-28 in the rear. My route encompassed 400 miles in 4 days of mostly flat terrain. I did have one mountain pass to climb which went fine. The gearing was fine with the exception of one hill where I was really wishing for one more lower gear. I found the extra cog over the 3X6 a nice thing to have.