They both have fans, so you will get mixed responses. We have stayed several times at CSR, but never at CBR.
A few of the differences:
CBR has double beds, while CSR has queen beds (don't know if CBR will get bigger beds by next year or not).
CBR has larger rooms with two sinks (340 square feet vs. 314 square feet). CSR has only one sink, but lots of counter space. CSR's rooms are larger than Pop's and the same size as POR's.
CBR has a great pool for little ones - zero entry, a kiddie slide, and a pirate ship splash area for kids under 48 inches tall.
CSR has a great pool for elementary and older kids and adults - the pool is large with plenty of room to move around, and the slide is long, open and fast.
CSR has the largest hot tub of any moderate.
CSR has a playground and sand volleyball court next to the pool. CBR also has a playground, but I don't know where it is.
CSR has a fitness center, salon, spa and night club.
CBR has a traditional food court. CSR has the Pepper Market, which is a quick service buffet for breakfast and lunch and a la carte for dinner. It is a great value on the dining plan, but more expensive than traditional food courts if paying out of pocket. CSR also has Cafe Rix (small, but open all three meals), Siesta's at the pool (lunch and dinner) and Laguna Bar (lunch and dinner) as quick service meal options.
CSR has sliding wooden doors separating the room from the vanity area. They are great for privacy and for reducing noise and light in the room when someone is getting ready in the bathroom. CBR has a privacy curtain.
Neither resort shares buses with another resort. CBR has seven stops. CSR has four stops. We have always had great bus service at CSR.
CSR is a convention resort, which means that you may see some people in business casual attire and wearing nametags. You may also find that the buses and the pool are much less crowded than you would expect because some of the guests spend their days in the convention center. I've only seen reports of one convention having a negative impact on guests, and it is always held in late February/early March.
So it depends a lot on your group.

If you have all adults or kids who are either adventurous swimmers or at least 5 or 6 years old, CSR might be the better fit. If you have toddlers or preschoolers, you might enjoy the extra floor space in the room for strollers (CBR has bigger rooms and smaller beds) and the zero entry pool.