It seems like a decent deal if you are not wanting to do it yourself, but I personally for that price would by my own detailing stuff from Adams and then you could detail as many times as you want. But just depends on how much time you have on your hands and if you want to just detail yourself. For example for the same price as that one year you could get this:
Adam's Premium Porter Cable 7424XP Detail Kit
Which really comes with everything you would need for a few full detailing jobs, then you would just have to buy the small maintenance bottles of like shampoo and such.