Hopefully Macybaby will be along and give some additional info. I think that a good indication of the differences for the VS machines is the tucker and ruffler.
Looking at
http://needlebar.org/main/puzzles/index.html it appears that the "spider" is in the same position on all of them. I got one that the spider was where the underbraider is and turned so that it attached to the very edge and both ends were broken off and missing.
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If you check
http://needlebar.org/main/puzzles/style7/index.html it shows the ruffler and tucker for the #7 box.
Janey - Neat people never make the exciting discoveries I do.