But dude, don't waste good cardstock on a test to see if it fits. Go to the search bar and look for the scaling thread, it will save you money and the enviorment. Try looking at the pepakura stickies, it will get you started!!!!!!!!
While the forums do have a lot of info on sizing, no person has the exact same proportions, so I'm all in favor of making low detail size testers. Card stock is relatively cheap at 3 to 4 US cents per page, and low detail models can be put together quickly, especially if you only use scissors and don't bother scoring your folds.
The pep file index definitely needs a section for size testing models.
Still, there are some on there, they're just not listed as size testers.
For example, supertaco's size tester chest is on there, but it's not listed as a size tester. Just look at the filenames.