20s for the Demon - how low can I go? (big wheel haters don't look)

I battled the thought of going with 20" out back also. Ultimately I choose 18" all around but still question if in should shove some twentys out back. I personally with the 18" in the front find it hard to see anything bigger fitting all that well. If you choose to stagger the rims. Like let's say 18" in front and 20" out back the key is to have the same amount of side wall on the rim. So you'll still be 2" shorter up front but it will blend if you have the same size side wall. Make sense?

Here's a video
https://www.facebook.com/video/video.php?v=104223156257688&saved