Both cane and corn sugars will leave some residual taste in the cider. Dextrose is a little more beery tasting, which is why a lot of people think it has a neutral taste (it doesnt, you just cant pick up the taste in beer)
I've done a bit of experimenting with different sugars and IMHO, the closest taste to natural apple sugar after it ferments out is a mix of 1/3 dextrose and 2/3 turbinado. The difference is pretty subtle though.
If you are fermenting to complete dryness, you are better off adding no sugar, you will get more apple taste. If you stop the ferment early, adding sugar can be helpful because the yeast will go thought the simple cane and corn sugars first (along with the simple apple sugars) and be easier to stop before it can ferment out the longer chain apple sugars (which is where most of the flavor is)