We've stayed at the CR twice--once Garden room, other Tower with MK view. We stayed for a long weekend at the Poly in January--Tahiti room with MK view.
We love the CR (Tower room especially!) for these reasons:
1. So close to MK you can taste the pixie dust! Watching Wishes from your balcony, hearing the sounds of the park--heavenly.
2. Just a short elevator/escalator ride from the monorail to your room. Much appreciated after a long day at the park.
3. A lovely 10 minute (or less) walk to MK, should you forgo the monorail.
4. The energy of the Concourse level is palpable. Chef Mickey's. CM's leading kids around on a pirate hunt. The shops.
5. We prefer CR's bathroom--separate room for toilet. Allows more use of the bathroom facilities.
The Poly is a very lovely resort, too, but we found the walk to the Ceremonial house (dining and shopping, plus monorail stop) was longer than what we wanted to do. In fact, we ended up using the TTC more than the monorail stop at the Poly. And the MK was too far away to really get much out of the view. However, our kids loved playing in the hammocks, and you can really get lost in the theming.
Both resorts have great-sized rooms, and the day bed works great for kids.
My suggestion? Try one now and hit the other on your next trip. Or do a split stay. Personally, my goal is to hit all the moderate and deluxes WDW resorts someday. But we'll always go back to the CR--somehow it just tugs on our hearts. We
it.
Have a great trip!