This is a not a comparison thread but I think SQ is way better than CX in Y.

I just took NRT-SIN in Y and I was surprised that they had a very large menu. I had a hot towel. A Wiseman on-demand 60-movie channel (you never get this on CX) and a Fauchon icecream. I am simply impressed. The only advantage I could think of on CX is perhaps a slightly larger in-seat TV screen and in-flight power outlets.

SQ also has chili sauce on every flight.