I urge you to take the test now!
To answer your questions:
1) Yup, your score will hang out in the "cloud" until you send your score to the b-schools of our choice.
2) No disadvantage to taking the test now; in fact, now may be a great time for you to take the test. Much of the material will still be fresh in your mind from college. Scores are valid for 5 years, as you know. Also, some firms ask for your GMAT score during their application process, so if you do score highly, it might be a handy bonus for you to have should you apply to another job.
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Economist GMAT Tutor