Splenda is the real surgar substitute which can be used for cooking and baking purposes as sugar.
Other sugar substitue like Equal , Sweet and Low, Sorbitol etc break when you bake or cook them.
I am diabetic ,I have made firni , kheer, gajar ka halwa, louki ka halwa , chanay key daal ka halwa myself succuessfully . My wife has made rass malai and other delicate mithais using it for me.