We went in July a couple of years ago and are returning this July (July 10-18 to be exact). When we went, we followed the Touring Plans pretty closely for the mornings, because that's how you get through the bottlenecks. The only exceptions would be skipping something none of us wanted to do, which the Touring Plans allow you to do. If you get to the park first thing, you are going to be able to ride those rides without using all the FPs even on busy days. One morning, we did not use the plan exactly through Fantasyland, and we waited in much longer lines than we had a few mornings before following the plans and I learned my lesson. So they really do work; for our entire week in WDW that time, we waited in no lines longer than 15-20 minutes, and that was in July when it was really crowded.
UG points out this problem with the FPs: you have to go to the ride twice, once to get the FP issued and then again to use it. That can waste a lot of time for at least one of the party to traipse and backtrack across the park. In addition, remember that once you get a FP, you're blocked from getting additional ones until your window is up, but again, if you have a good Touring Plan (like in the book), you won't need all those FPs.
Here's when I'd use FPs more than the plans indicate--basically in the afternoons or evenings, if I want to revisit a ride. My kids loved Buzz last time and wanted to do it more than once. So we did our morning commando UG Touring Plans thing through the big rides but then we got FPs for Buzz for later in the day; that was just an extra thing, though, and it would fall into the UG's part of the day to revisit favorite attractions. But beyond that, I stick to those plans and really like them.
By the way, my entire family thought I was nuts when I started the trip, but now my husband swears it's the best way to see the parks, and he trusts me completely to lead them around!
I really, really want to stress how well they work, even if they seem like a pain in the neck. Have fun on your trip.
