What difference does it make close to the end or not. People in on the project deserve to see how it's moving along and to help them decide if they're happy with it or not.I'm only talking about very small tweaks that wouldn't make a huge difference to the final prototype. I would much rather show the end product that we're so very close to then the current WIP.
There is literally no harm in showing it. What's gained by holding back the updates.