Not only as a demo, but it would be awesome to have objects that test my printer for the great new features. Like bridging perimeter options and variable extrusion sizing; both are hugely great features, thank you very much for creating these! But what are best settings for my printer? I rather print one test object, even if it might be big and time consuming, to find out the settings than try to print several real items and still wonder if I have my settings right.
For example, I would think that to test the variable extrusion sizing, I would try to print a knife like object, with sharper and shaper edge, noting where the print fails. The step before the fail is the best my printer with the current filament is capable of. I get the warm and fuzzy feeling that I have the best setting, and I achieved it with one test print.
Now that I wrote about this, I realize that I would actually pay for this.

So, please, you know the features better than anybody, so you know what kind of an object best finds the settings. How about it?