Preliminary sales results from Best Buy reveal that Samsung’s Instinct is a best-seller for the retailer. In fact, a company spokesman said it has sold better than any other phone the retailer has carried since the Motorola RAZR which launched in Q4 two years ago. Both phones, he said, produced similar sales figures.

Although no specific figures were provided, Best Buy indicated that Sprint’s multimedia device produced “record sales” in its first two weeks, which has also seen its sales of higher-end, multimedia phone increase tenfold in the past year since Best Buy Mobile began its national roll-out.

Best Buy Mobile was created as a joint venture with leading U.K. mobile retailer Car Phone Warehouse two years ago. The national retailer instituted Best Buy Mobile, its new wireless retail experience, to offer customers one of the widest selections of wireless carriers, phones and accessories in the United States.

According to Shawn Score, president of Best Buy Mobile, the stores carry up to 95 different phones and customers are increasingly buying feature-rich handsets that let them do more including e-mail, Web browsing and GPS navigation.

As part of customers’ purchase, Best Buy Mobile is extending its Walk Out Working program exclusively to all Instinct purchases in July and August. The program provides multimedia and smartphone setup and personalization so that  the device will be ready to use immediately.