well, if you are going to do long-distance touring with hundreds of miles I would recommend upgrading to a bike with Ultegra instead of the 105's that are on this bike. I rode across the USA twice and I had 105 on my Independent Fabrication Crown Jewel bike and then last year I rode across again and had the Ultegra components on my Trek Madone WSD 5.2 bike, 10 speed, triple crank. So smooth shifting, so very durable for the long haul. I had an 11-34 cassette with a mtn bike deraileur on the IF bike -- made going up mountains (The Rockies - and in NH and VT easy). On my Trek since it is a 10 speed I switched it to a 12-27 cassette. It was sufficient for the steep hills and mountains.
Hands down the number one thing is to have a PROFESSIONAL fit done. I've found precious few local bike shops that really know how to do an expert fit. This is key to your comfort on the long touring days. I went out to the Boulder Colorado Center for Sports Medicine and Dr Andy Pruitt did my bike fit. It cost me $185, and worth every single penny. Took about 2.5 hours. He's the expert. He fits the top cyclists, like Lance Armstrong, Tyler Hamilton and the USA Cycling Team. You can ride for hours and hours and never feel uncomfortable. An expert fitter knows just how to get your body and the geometry of the bicycle to be 'like one'. You'll often need to have the stem on the bike changed to be much more comfortable, and the fore and aft and up and down of the saddle have to be perfect or you'll be sore and uncomfortable on long rides. And your cycling shoes, if you are wearing clip-in cleated shoes/pedal system - they have to be in just the right position so your toes don't fall asleep, and so you also get the maximum power out of every pedal stroke. Hope this helps some. Again, the most important part of getting that bike is having the very best of bike fitters do a good fit for you.
Riding over 10,000 miles per year - many muliti-day bike tours and bike club riding through out the year. 63 year old female.