720p vs 1080i: which scales better?
 

Which will likely produce a better end result:
720p scaled to 1080i, or 1080i scaled to 720p?

Scaling downwards is virtually always the best option.
There are loads of free files here on DVInfo.net and VASST site, plus other sites that you can experiment with.
The VASST site has JVC and Panasonic-acquired footage that you can up scale, and Sony/Canon footage you can downscale.

And don't forget to try converting both types of footage to 1080p.

I must be blind. I looked on both sites and came up empty. Can you lead me by the nose to this footage?