I'd commit if it was the school I really wanted to attend. If my only options were MAC level schools I'd wait to see if something better came along. (although if a good school was filling up, and that school was my top choice of offers outstanding, I'd prob. verbal to that school to secure a spot... ie. if Duke offered and I only had offers from Ohio U, Miami, Toledo, BG, and Duke... I'd verbal to Duke if their class was filling up/my position was filling up).
If I ever received an offer from Stanford, I'd verbal on the spot. Nothing like the second best education in the nation free of charge
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