No doubt refurbished products, like second-hand cars, can be a good investment. But not always: read http://www.cnet.com/forums/post/08085adc-0d9e-4bf2-bfa6-11e32308a4c1/
You need a trusted shop that gives a good warranty.
I just wanted to share my experience of buying refurbished products from an Indian shop. I have bought 2 mobiles and 1 Laptop from them, at almost 30% discount on market price. All the devices are working perfectly and they even are in warranty.
This makes me wonder why do we all buy new phones at such an exorbitant price? Refurbished products are awesome at the price they are sold at.
So be smart and buy smart
Note: name and link of shop removed by moderator. Those aren't needed to make the OP's point.