Thinking about replacing the T2400 CoreDuo (No, you read that right, it's a Yonah) with a T7200 Core2Duo (Merom). Was researching a bit, found that I could grab a used processor for about $50 cheaper than the approx $140 new price. Thoughts on whether refurb or used are worth looking into? spending $50 more isn't a huge deal, but every bit I can save helps