Worth is hard to put a value on. If you are looking to save money, conc. is probably not going to be "worth" it for two people. However, if you want to be pampered a bit more then normal, then yes it's worth it.
We stayed at PP, conc. level in Oct. There was 6 of us. It was great to be able to eat a quick breakfast, and take drinks to the park. Most of us only made it to the evening snack and drinks once. My FIL went back to the park almost every evening for it. The kids loved turn down service and the chocolates on the pillow.
We had a choice for our stay, either PP conc level or a very standard room at GC. What we really wanted was a regular room at the DLH, but it wasnt available for our dates. If I had it to do over again, I would have went to GC non conc. The walk back and forth to PP was long, and the breakfast and drinks werent enough to balance it out. However, the rooms at PP are bigger and the view of the park was really great! I guess what I'm saying is, it's all about whats important to you, we all put values on different things.