I don't have a membership here and have just started using the forum this year as a test run for whether I want to join or not. I currently do pay for a membership on another board and have for over a decade and am contemplating a switch. To be honest though I'm not sure it's worth it to pay for any sites since there is so much info out there now and if you've been playing this long enough you know how to use the free stuff and benefit from it. There really isn't anything I'm currently getting that is giving me much of an advantage then if I just used the free info.
I will say though now that there are probably at least 6 owners in my local leagues that all belong to the same other site that it was nice being at the draft with a different sheet and info than them.
This may sound odd coming from someone who generates content for FBGs, but I really believe that you don't buy a subscription for the content, you buy it for the tools. The content is just a really nice freebie thrown in on top.
Lots of other sites give excellent analysis. Much of that analysis is available for free. Guys like Mike Clay, Evan Silva, and Josh Moore are superstars in the field, and none of them work for FBGs. Bryan Fontaine and the DLF guys are all huge resources for dynasty leaguers. There are a ton of smart guys under the FBGs umbrella, and I'm honored to count myself among them, but I don't think anyone around here would ever suggest that there aren't an equal or greater number of really smart guys who don't fall under the FBGs umbrella, too.
In my mind, what sets FBGs apart are all of the "extras", the stuff that goes beyond analysis and predictions. The Draft Dominator was revolutionary when it first came out, and as far as I'm concerned, it's still the best drafting program on the market. The new iPad app (which, it should be noted, is a separate standalone purchase independent from a FBGs subscription) is also a really powerful, intuitive drafting tool. The Data Dominator and Historical Data Dominator are pretty much the best / most powerful / most comprehensive statistical databases a layperson is going to have access to, outside of the PFR play finder (which is more limited in usefulness, but much broader in scope). Now that they've set up myFBG to sync automatically with all your leagues, that's the real money feature, though. No matter how many leagues you're in, you can link them all up to FBGs, and every week it will update with the most recent projections to tell you who the best free agents are IN EACH SPECIFIC LEAGUE. It will calculate and recommend who you should start and sit based on your specific scoring system. I find this year that, by using myFBG as the beginning point of my weekly process, I'm probably saving a good hour a week per league. With 6 leagues this year, that's six hours a week. Over 16 weeks, that's nearly 100 hours that I'm saving thanks to myFBGs. I don't know how everyone else values their time, but if I can spend $30 on a product that saves me 100 hours, I consider that an absolute steal. Adding all of the other stuff on top is just gravy. Delicious, delicious gravy.