I have the Sizzix Big Shot Pro. I use regular Go dies in it. I did a little experimenting when I got the first Go die to determine how to configure my adaptors and shims to get the best cuts. The thing I like about the Sizzix that I've got is that I can use just about any dies on the market with it--which means I can use the machine for cutting more than just fabric. Someone else mentioned that they have used the Studio dies in their Big Shot Pro as well. The Big Shot Pro does take up a fair amount of space. I have a dedicated space in my studio for it since it is too big to be easily storable.
The small size Big Shot would not be able to use the thicker dies, but it takes up less space. Some of the Go machines fold, though I think the Studio does not--it's comparable in size to the Sizzix Big Shot Pro.
If you only want to use the Go dies, then any of the Go machines would work for you, unless you want to use the Studio dies--I'm pretty sure they are too thick for the regular Go cutters.
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