If you are a standard user, the "best" way to get Update 3.0.3 is through the official Nintendo servers to ensure your account stays in good standing. If you are a power user looking for archival purposes, the NSP/RAR route offers the convenience of offline storage and potentially faster load times if moved to the internal NAND.
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were characteristically brief—stating only that "several issues have been addressed to improve the gameplay experience"—the community's digital detectives quickly went to work. The Hidden Fix If you are a standard user, the "best" way to get Update 3