I don't think there is a 1512 1Y. Do you mean 1512 2Y? 1400kv motor? If so, I would imagine that it would be bad a$$; and I mean that in a good and bad way. I've found anything more than 4S to be good for nothing but speed runs. It's even too much for bashing. The torque is insane. With my 9XL on 5S, just blipping the throttle too hard puts my truck on its roof.

If you go with the 2Y on 6S lipo, all I can recommend is Gorilla glue for the tires instead of CA, and forget about bead locks. Or actually, maybe bead locks AND Gorilla glue.