I love my go.. I have almost all the dies ( minus a few applique ones) I too have many back up mats as I go thru them quickly.. But Ill use the larger mats when they can no longer be used for the larger dies and use it with the smaller dies.. As long as the die is covered doesn't matter which one i use.. As for the the cost of the dies.. accuracy and less fabric waste makes this a bargain for me..