Those look great. The muzzle break on the first & third ones seems different, or is it just the pictures?

There are many different muzzle brakes being run and tested on the MDR currently.

Here are some more pictures for your viewing pleasure:

All of those look great. Is this the final production MDR, or are there still more changes to be made?

Those are pictures of the production MDR yes

That is excellent news. Is there a public ship date for the first batch? I have a pre-order with an anticipated delivery of the end of August, do you expect that date to hold, or will there be a delay on that as well?

Very nice, I like the smaller red-dot style sight; perfect for fast maneuvering. Especially in tight places.