I 'm a big fan. I've been using their plans since 1989 and get a subscription every year that I'm going to WDW. My 20 year old and I have so much fun putting touring plans together and tweaking them. // Before I decide on dates, I look at what the waits look like for what I want to do, and for example for March -- Keys to the Kingdom at the MK till 2 and then 10 attractions even with a few FP+ things just didn't look appealing (too many long lines projected), but DS is off of school till the Martin Luther King Holiday - -long Christmas Break and the time between the Disney Marathon and the MLK holiday looked great (I would be OK even without fast passes lol). The plans really helps to level set expectations, see what you can get in in a day. // The phone app is fun too. // I also like the site descriptions of all the rides and the ratings of everything by age. // Also with a large group, a touring plan that the core group will do is worth it's weight in gold vs. way to many people discussing and deciding on the spot what to do next. A few folks instead with everyone's interests in mind come up with a core plan, distribute it to the extended family and say they are welcome to come with us on this for all or part of it and/or do their own thing. And we usually end up with about 10 of us following the plan together.
My testimonial is that I did the MK over Christmas without the plan, arrival 90 minutes before rope drop and all that and the lines and crowds were unbearable -- really got me down.
Same day at the MK a year later with the touring plan and what a difference. I actually had fun during the busy Christmas time even. Still avoid Christmas week if you can.
The Unofficial Guide book is a really fun read too and spot on with great information.