SO it's set then...

SQ's 37" vs CX's 32".

Although I must add that SQ's Executive Economy Class is a tad more expensive than CX's fares. Given the distances and time travelled, I'd opt for SQ over CX.

SQ's economy class service is marginally better than CX. And I hate to admit it that SQ's IFE Wisemen has a lot more choices than CX's Studio CX. Though the latter is easier to navigate than SQ's.