You are not going to even be able to get close to the performance of the 8XL with the 1512 2Y, unless you move to a higher voltage setup. I recently got in a 1.5Y that was mislabeled. I believe it was actually a 2Y, judging from the performance. On 4S, I ran a 16/44 gearing and it was a bit slower than a 9XL on 4S running 14/46 gearing. If you are running the 8XL and want to stay close to that, I'd get either the 1.5Y or the 3D. You could even go with the 2.5d at a 2000kv rating. I feel that the 2Y is strictly for mild running or a high voltage (over 21v) setup.

Any Neu would be better than any Feigao, just because it will run cooler. It just may not be as fast, depending on what you get.