Depends on your wants.
We were just there in September and toured both. It had been a few years since I'd visited either.
CBR - Loved the new pool and new hot tub/cool spa! We didn't go in, but they looked really nice! Super Clean! A good hot tub is something we really value in a resort. We'll probably never stay at the Poly! The new water park area looks really cool. The pool has two water slides, a tame one and a more adventurous one, plus several mini-slides on the water playground part. The food court is colorful, and has some unique food items. There was a fun game of limbo going on while we were there. CM's were playing music and clapping.
The food court is set up in a fairly efficient manner. I like the way it's set up. Each area is clearly defined, and it's easy to get your food. Tehre's a single cashier area, so that could be a bottle neck at times. But overall, if getting food quickly is a priority, then this food court will probably be faster.
Then we drove around this resort. It is BIG, and spread out. I really like the new pirate themed rooms, but they are far from the main building. You'd lose lots of time walking from main building to those rooms. I love the idea of queen sized beds at CSR.
CSR - After two really bad meals (Tusker and Chef Mickey's) We decided to try dinner here almost out of desperation. I remembered the food being good, and hoped it hadn't gone as far downhill as Checf Mickeys. CM was REALLY BAD, IMO!
WE were able to get a bowl of strawberries; fajitas with salsa, lettuce, beans and tomato; a really good pizza (WAY better than pizza elsewhere on property); and a steak that acutally came with nice green beans!!!!! Wow real veggies!!! All using QSR credits! (though the strawberries were considered an extra snack.) It was a slice of heaven! After dinner, we opted to take a slow walk around the grounds. Yes, CSR is large, but not as rambling as CBR. On one side of the circle is the pool, on the other is the food court. So if you are away from main buliding, at least you are close to pool. Both are pretty resorts, but I think CSR at night is really pretty. CBR is prettiest in daylight. In some ways the theming is similar though.
The main pool and hot tub at CSR aren't as new and splarkling, don't have zero depth entry, don't have the new water playground. I still think the pool at CSR is exceptionally pretty with it's pyramid, but it's mostly something to look at, rather than somethign interactive. The water slide is good.
Adjacent to the Pepper Market dining is a bar. It's enclosed now (in the past you see folks drinking while you dined), but there is still a bar with adult conference attendees milling about. If you like the bar aspect, we didn't go inside, but the lighting/decor looked pretty cool.
There's pool bars at every resort, so you will always see some folks drinking at all resorts. At Pop, the pool bar crowd was especially prominent. At AKL, it is MUCH more discreet. These two resorts fall in between. Some folks find drunk conference drinkers more disturbing. I personally find obviously intoxicated parents slightly more disturbing. I don't mind some drinking, it's just that lots of obviously blitzed strangers are a somewhat disturbing sight at WDW....
In truth, CSR is probably just as big as POR, but it doesn't feel quite as big to me. At both, I recall that we were able to park very close to our room. I also recall that at both of these (unlike POR) the nearest bus stop was very close to our room.
