Only if you don't use it. It's very worth it, the first time you do use it. It's cheap insurance.
Read the fine print. There are a number of exclusions, which grouped together, effectively state that the plan is under no obligation to do anything for you. You are entitled to six hours of counseling, but ultimately the representation by the plan attorneys will cost you. It also doesn't cover any appeals.
Because you are dealing with administrative law when considering certificate actions and enforcement proceedings, you have nothing but appeals. The plan quietly states that it doesn't cover you in the areas you need it most. Weather it actually does, or not, is another matter. The point being, it doesn't have to cover you.
The insurance services offered through AOPA are surprisingly similiar, and don't cover you if you're flying an airplane, or in an airplane, other than as a passenger on a commercial carrier. I called AOPA to query them on that, and they didn't have much to say.
Then again, AOPA does a fine job of talking about themselves, but unfortunately doesn't have a lot of punch where it really counts.
I had the plan for awhile, before I was in ALPA, which has a plan of it's own. I used it only once, and I felt that it paid for itself. Sometimes, it's nice just to have someone well versed in aviation law to speak to. I think it may have helped me circumvent a violation, or at least made me feel better about the situation. I feel that it's pretty cheap for what you get. Hope this helps.
Shop around. In this day and age, every pilot needs some form of insurance. Try AVEMCO. In my two-center opinion, and based on my experience working for a plaintiffs' lawfirm, you do need good liability and hull coverage, but what's more important is a legal defense. It may be worth it to fork up the extra bucks for a policy that states that you will be provided with a defense if a claim is made against you.
Flight instuctors especially need a good professional liability policy for the same reasons.