After Apple launches a new product, it often takes a few months before they are able to build up enough stock of defective and returned products to start selling refurbished versions. Apple has apparently collected enough stock of the latest iPad mini and fourth-gen iPad as they are now available through Apple's online store.
Stock of the refurbished products is still constrained. Customers are limited in selection as the WiFi-only iPad mini is only available with 32GB of storage. The WiFi + LTE is available with only 16GB of storage. Moving to the fourth-gen iPad, users can only select 16GB or 32GB versions of the WiFi-only and WiFi+Verizon LTE models.
Furthermore, the discount offered by buying refurbished isn't that great. On the 32GB WiFi iPad mini, users only save $40, or 9 percent. On the 16GB WiFi+LTE, users only save $30, or 6 percent. It's up to you to decide whether these savings are worth buying a refurbished product.