You use just a tiny bit more. The taste difference will be mostly negligible although it is possible to have a super faint taste difference if it is vastly different from the original brew. I personally like to carb with DME as the bubbles seem to be finer but that could be a subconscious association to be fair.
As was posted above, NB has a really terrific carb'ing tool link. I usually go with 2-2.5 volumes in the beers I make but if you've got one that requires less adjust accordingly. Just remember, standard beer bottles are only rated for like 3-3.5 volumes or something like that.