If RESCENE hits 500k in first-week sales, it's a huge success.

Considering how idol agencies "pull forward" first-week sales (making sure sales that would happen later are counted in the first week), hitting 500k would be a massive success.
Assuming there is no pulling forward, it would be 300k. (But there's no way they aren't doing it; they pulled forward sales to hit 100k for the last album, too.)
Since RESCENE has almost no international fanbase, hitting over 1 million is simply impossible. Even Lim Young-woong's peak fandom, which was incomparable to any other domestic fandom, only sold 1 million within Korea.