Ah.. I see! Well I think B_button_member is right then. D/P, since it has Wi-fi, will take a long time to get old. Considering how Sapphire has kept me busy for 500+ hours and Ive only recently restarted, Im pretty confident that D/P will have even longer. So Id say by all means, transfer her over! You could use her in battle tower, E4 training and ... what the heck! contests, too! And, you could probably restart your Emerald to get another Latias like Ive done! Sassy is a pretty good nature, although the decline in her speed may hurt her a little. Depending on which stat you wanted to raise, if you had the time and patience, you could go out searching for a Bold, Timid, Modest, or Calm Latias! ...Unless you happen to want to use physical attacks with her. =/