I don't know how you define "worth it" - but we stayed there over Thanksgiving last year and we really liked it. We are planning a September stay as well.
It is usually multi-hundreds more over the course of a trip vs. staying off-site, so I guess only you can decide if it worth the extra money to you.
I think if you are only planning to crash out at night there, maybe not. But if you want to take some time to relax at the pool, or drive the little boats, or watch the fish, then yes to me it is worth it. It seemed a nicer "overall" vacation experience to me than staying off-site. Plus for a longer trip you can make more use of the MM.
We are also going down a weekend (fri night-sun night) in August and October. For those we have chosen Hojo because we will not be spending much time at the hotel (a little in August to use the cool kids pool!) but mostly we are going park commando those trips.
I say if you have a good rate, you can afford it, and you've always wanted to stay there, then go for it! If the rate was crazy or it puts you into debt, then I say go cheaper.
Kim
ETA - too funny! Our last WDW was at the Poly, and DH just returned from a quick trip to DLRP and he stayed at Val D Europe too!