You're going to need 100g of DME for a 1l starter. If your recipe can spare that much and not be effected greatly, go for it. I just buy a 3# bag of plain light dme and use it for starters only.
__________________ "This is grain, which any fool can eat, but for which the Lord intended a more divine means of consumption. Let us give praise to our maker and glory to his bounty by learning about... BEER." - Friar Tuck
I've taken LME from a batch to make an emergency (read; lazy and didn't want to go to the store) starter, then once it fermented just pitched it all into the main batch. It works fine, but tedski's advice is the best way to go.
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