Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Warning: Do NOT purchase these from Amazon

Amazon will not stand behind their delivery contract. I purchased this item, eight days ago, paying for "expedited" 3-day delivery; as I had a deadline which is now long past. The product still has not arrived, and amazon sidesteps responsibility for the sale; instead, redirecting the buyer to the subcontractor - despite the fact that Amazon is the selling party. The product is excellent: I suggest Best Buy, Comp USA or any one of a number of other suppliers.