Wi6Labs have posted to another thread saying they will fix the issues, and make the board run at the correct speed, 80MHz
I think they said they will make the SPI speed default to 5MHz,which is higher than the AVR Arduino but I think this will be OK, as most devices will run at greater than 5MHz.
SPI speed is often set in the library for a specific peripheral eg. LCD screen, but these are often written for AVR, so need to be modified to support any other boards, even other Arduino ARM boards , like the Due.
But this is becoming less of a problem as more people use higher speed devices and libraries are modified to work with a wider variety of processors.