I used it (touringplans.com custom touring plans) last Wednesday and Thursday (Wed. for
Disneyland and Thursday for CA Adventure). Our plans of must dos only went to about 4 p.m. in both parks. Wait times predicted were a little off as they had predicted crowd levels of 2 where the actual crowds when I looked back were level 4 for our Disneyland day and level 1 (lots of rain) for our CA Adventure day, but the rain closed down a bunch of rides making some open more crowded I'm guessing. With all the extra time we didn't have a plan for, that was no big deal. The plans worked like a charm for fastpass suggestions -- it told me to pick up an Indiana Jones fastpass and then go on Pooh and Splash Mountain, and then return to Indiana Jones to use my fastpass (unbelievably the timing was absolutely perfect.) The fastpass had a relatively short return time and after those two attractions it was 10 minutes over the return, so perfect -- 10 minutes into my hour window. // At CA Adventure too, I was super tempted to just go on Soarin first thing (no line at all), but the plan had me pick up a fastpass, then go on Toy Story Mania, California Screamin, and Ariel's Adventure at the back of the park (short lines), pick up my world of Color fastpass, and then go back to Soarin and use my fastpass (I followed the plan and again timing was perfect. By the time I got back to Soarin the line was 50 minutes long and we just walked on with our fastpass). I would have never done things that efficiently on my own for sure. // Later, though, it said to go standby for Radiator Springs Racers (25 minute wait predicted). The line by that time, however, was 50 minutes, so we picked up a fastpass instead with a pretty far off return time (over 2 hours) (We were already near the end of our touring plan and didn't have any other fastpasses recommended to pull). We then ate lunch, looked in gift shops, did Bugs Life, did California Screamin and Ariel again (both lines were short - California Screamin just because it had been down and restarted when we walked by.) Then we did the Racers, took an afternoon break, and came back for a few hours in the evening. At Disneyland we stayed all day and did little kid rides in Fantasyland and character meet and greets after our must dos on our plan were done, as well as have dinner in the park. We also watched the Dapper Dans.
Overall, I'd give the plans a letter grade of a B and say that they were worth it for me to have (Do note that I hadn't been to Disneyland since 1964 when I was four and that I had never been to California Adventure, so a little guidance really went a long way for us). Usually at WDW the wait time predictions for me have been more accurate than they were for me at the Disneyland parks FYI. Even at WDW, although touringplans.com often nails it, there are times when they can be way off there too.
Side note: I've been using tourinplans at WDW since 1989 and have been to WDW over 20 times and am a really big fan of them for WDW.
