In essence, this is a copy of the late war German all-steel "resilient" wheel - although that was driven largely by the shortage of rubber and used an early form of synthetic rubber between the metal plates.
As you say, it completely gets around the wearing-out of rubber tyres by whatever means, and the rubber bushing lasts considerably longer. It is also very probably field-replaceable, unlike rubber rim tyres. A couple of inches of hard solid rubber gives little shock absorbing to the vehicle systems and occupants anyway.
It does, however, make a far noisier vehicle if the inside face of the track is also metal - which it looks like it is on all post-war Russian tanks. Track wear may also be increased, with the inside face becoming grooved over time, potentially shortening track life compared to using rubber-rimmed wheels. Compromises, compromises......
Regarding painting, I imagine the steel alloy used for the tracks and wheels will have a high Manganese content for wear resistance. This means that the wearing surfaces of the wheels and both faces of the tracks will not be bright silver, nor will they be graphite metallic grey. High Manganese content steel has a goldy-brown appearance, difficult to replicate and for which I have not yet found a stock colour match.