I have stayed at Poly many times and CSR once.
Right now I think if they were both the same price I would choose CSR every time.
Some people like the deluxes because they have interior hallways. I get a worse night sleep at places with interior hallways than anywhere else. Early mornings and late nights kids AND parents bounce off the walls, run, yell, scream, bounce balls and it never fails I'm awakened by this. There is always some nitwit guy who doesn't want to disturb his family in the room while talking on his cell phone, so he goes into the hall and paces while shouting into the phone. It never fails that I'm opening my door and telling someone to keep it down.
The CSR has, in my opinion, a better pool area...larger, WITH a hot tub.
The Poly GCH is ALWAYS over run with wall to wall people everywhere. Because of the popularity of the location and 'Ohana, it just seems like the joint is always crowded as heck.
To me, I don't see enough difference in Deluxe, (And deluxe-lite, WL & AKL), vs Moderate to even classify them that way anymore, I just choose based on what I like.