Fast Saving of Custom Class Array

Is there a faster way of saving an array of custom matlab classes than the built in save function?

I have an array of instances of a custom class each of which has two properties containing matrices of dimension about 600x800 [double]. I would like to be able to save and load this array as a variable although the built in save function is very slow. Using '-v7.3' formatting it takes around 1 second per array element. This array will eventually be hundreds of elements long. Is there a faster way of saving and loading objects?