I have two Shimano dynamo hubs. They are excellent. The one you identified should work well.

To convert the dynamo power to DC so you can charge your phone and Kindle, you need a converter. There are many options with most costing more than $100. I use the Biologic Reecharge converter, it costs only $30, offers a USB plug, and works very well.

ReeCharge Dynamo Kit with Micro-USB Cable | BioLogic Bicycle Accessories and Bike Gear

I have tested this converter with two items, my Nexus phone and a battery pack.

I found that my phone, with GPS running (Mapmyride), but in airplane mode and screen off, charges at about 1% per mile. This means it gains charge even when using it to track a ride with GPS. Obviously the charge is faster if the phone is turned off.

What I have found is that I can GPS track my entire ride with my phone, but for the first half of my ride, I can use the dynamo to charge a spare battery, then for the second half of the ride I can attach the phone to the dynamo and recharge it back to full. That's efficient work.

My findings above seem to match the findings of someone who used a different dynamo system, but obtained similar results while riding the Great Divide route. This person recharged an iPhone via dynamo exactly as I outlined above. Quotation:

"I was able to charge my phone within about half a day of riding."

Schmidt's SON 28 15 Generator Hub Review ? Small Tomatoes

I think dynamo systems work very well.