''As to '' is defined as in the same meaning with ''About'' All WH- quesitons I seen , are used with ''As to''. İs it more idiomatic to use ''AS to'' with WH- questions than ''About'' EG; A1)He was uncertain as to which roadto take. B1)There's no decision as to when the work might start. A2)He was uncertain about which road to take. B2)There's no decision about when the work might start. Are both sentences correct A1 vs A2 and B1 vs B2? Which is prefered by a native ; as to +wh- question or about+ wh-question ??