Mcdvoice is an official site where valuable customer insights from the Survey will help restaurant like McDonalds to understand & satisfy customer needs and behaviour. These customer insights will be taken into consideration by www.mcdvoice.com.  As Mc’D receipt is valid for 7 days, Customers who participates in the customer surveys within the timeframe are eligible to win free sandwiches. However successful restaurants run on understanding their customer satisfaction and providing high quality services to serve them better.