I was lucky enough to get a look at one a few years back when I visited a very good, mainly civil aircraft collection in the city of Ulyanovsk. Highly recommended. The concierge guy was kind enough to open it up especially so I could get inside.
It was only then that I learned a notable point which can be distinguished from the video. The 144 had 5 abreast seating as opposed to Concorde's 4.
Remarkably curved wing too. What a brute of an aircraft!
Cooch