I have stayed at both and both are georgeous hotels.
Poly rooms are more spacious, but I preferred the bath layout at AKL where the vanity is outside the real bathroom.
I love that AKL is in a world of it's own, some people call it too far away. But for me it enhances the theming. The Poly is more a standard hotel for me as you can see GF, MK and CR from there. But then, at the Poly you have a lot of things very close by.
I loved taking the boat to the MK and the Monorail to Epcot from the Poly. But we did not like the busses at the Poly at all. The additional stops were annyoing and in the mornings we twice had to wait over 30 min for a bus and nearly missed rope drop due to that. At AKL we always found the busses very reliable.
I personally prefer the pool at AKL, love its theming. The volcano pool at the Poly is nice, but we found it very crowded, even on rather chilly January afternoons. I once went swimming in the morning and that was fantastic! The second pool at the Poly is ok, but nothing special. Also, the Poly does not have a hot tub.
Kona Cafe is a nice restaurant, but I prefer the AKL restaurants.
In the end I think you would have a wonderful stay at each of the two resorts, but for me personally I would choose AKL. But then, if you think that this might be your chance to stay at the Poly for a halfway reasonable price, I would say, go for it and experience it for yourself!
