Sizzix can use both. Accuquilts dies are thinner so sizzix can't be used in them, however their smaller dies tend to be wider so not all of them can be used in the big shot due to the width so if you have the funds I would invest in the big shot pro. I just have the big shot, have no issues with it, just don't care for the cost of dies and now that I have my scanncut don't really need it but do have afew dies like the drunkards path and rag die plus a few appliques