Simple as AK-47, comfortable, like any bed after Vodka and durable, like bear fur - this is the best description for any Russian Army Bodyarmor. Their main aim - protect soldier, be cheap and simple and of course be comfortable for multiple day use.
Defender - one of the main and one of the most popular Russian Bodyarmor. Used by FSB, sometimes police units, army and another structures. Very comfortable, affordable and nice bodyarmor. If you are just starting making your Russian Kit - that's they best choice.
Here you can find more modern Generation of Defenders - Molle Defenders. They are created for Special Force, who prefer to put pouches directly on Bodyarmor. Plus here you can find modified defenders, from SRVV and Stich and etc.
Police (MVD) Bodyarmor
MVD (Police) bodyarmor usually simple and provide maximal comfort and mobility. It's main aim - provide basical protection against pistol bullets. That's why the main aim of this bodyarmor - comfort of the Policeman.
Everything, what wasn't included in other categories. Like Specops bodyarmor and etc.