I have taken several classes at FS and would say it was definately "worth it" for me. The "worth it" measure depends on where you are coming from - both in terms of training and ability as well as geographical location. It also depends on if you are using time or money as your "worth it" measure.
IMO FS provides a very proffessional, organized set of basic classes that are excellent for anyone who has had little or no previous training. They also have more advanced classes (that I have yet to experience) but that I believe are quite good as well.
If you are in the NV/CA area it believe FS is definately 'worth it' is terms of time invested and, since the cost is relatively low also for the $ stand point.
I am in TX and every class I take requires airfare, rental car, hotel, meals, etc. so that is a higher standard in terms of 'worth it' from both a $ and time perspective. That said, I have taken the 1-day sub-gun class, 4-day defensive hangun, 2 day defensive handgun, 2 day handgun skill builder, 2 day practical rifle, and a 2 day edged weapons class over the past 5 years. For me these were all worth it even with the travel costs. I have always learned something new or increased my capabilities from every class.
[As a side note: regarding FS business practices and other 'issues' I have NEVER had any problems or detected any hint of a hidden agenda while at FS. There is some 'sales pitch' for memberships but it is low-key and can be skipped if you wish. It is not like a timeshare pitch where they block the door and you can't leave until they have beaten you into submission mentally.]
Get a grey certificate (typically less than $100 on ebay) and try your first class. (Note there is also a $50 background check fee per year). If you like it you can go back, if not...hey, a few days of shooting is better than most ways to spend your day.