I have to say I am loving using the tumbler die I got with it. I liked the smaller GO! since I am short on space {as in an ikea hutch is where all my stuff live, fabric is stashed in closet}.
The smaller piece sizes isn't an issue so far since I am using it to cut down odd sized scraps into usable things. I wish I had grabbed the square dies, as I am now loving making tons of Half Square triangles by sewing twice along the diagnoal cutting line. That would have been a real help.