The export is only the first step, not the migration. A file from the admin will not tell you which addresses actually exist, will not build a new design or product pages, will not create the redirect map, will not carry over the logic from your plugins or connect your carriers, feeds and invoicing – and it will not check whether prices, stock and variants still add up after the import. For a small catalogue with no history and no rankings, I will talk you into doing it yourself. For a store whose revenue rests on organic search, the cost of a mistake usually runs higher than the cost of the migration.