Buran never flew with humans aboard. The one prototype is gathering dust somewhere in Russia. We could design and build an improved shuttle before Buran ever saw daylight.
They may revive it.
Russia To Bring Space Shuttle Back From The Grave
It appears they're putting some of the money from commercial satellite launch back into Buran. And they have a large base still stocked with parts and a Buran that is still ready to fly.
I'd love it if they flew it. Our shuttle only carries 20 tons. Theirs is huge and carries over 100 tons. By extending the length of Buran (now being planned), they could carry 200 tons! Just imagine what it would be like to see such a monster space plane in flight. Wow!
This is the kind of vehicle that we should have. We should buy it up and use it for ourselves. If nothing else, the Energia launchers alone would be a great acquisition for us. The Energia launchers could have lifted the entire space station in 3 flights instead of the 38 it will take our shuttle to do it.
Look at that monster!