From what little I know about Russian Blue's, I've heard they're a fairly mellow cat, and somewhat delicate, and petite. Am I right on that? If I am, I don't think a Bengal would be a good match. I LOVE Bengal's, I have 2 of them, but they are high strung, extremely playful, and unbelievably active. They're loads of fun to have around, but I just don't know if a Bengal would make a good companion for a Russian Blue. My Bengal boy Simba, has my huge Siamese cat who is about 25 lb's, totally intimitaded. Simba is alot smaller than my BIG boy, but little Simba who weighs about 9 lb's, pounces on that cat all of the time, and has him running for hiding places. Now, Simba isn't mean, but he does enjoy a challange, and since my big Boy Shane is such a challange, Simba doesn't let up. The more upset Shane gets, the more Simba goes after him. So, I would say, it depends on the personality and stamina of your Russian Blue, as to whether you should get a Bengal. I have another little Siamese girl, and she and Simba are great friends. She chases him back, and they love each other. So, it just depends. But I promise you, Bengal's are a handful, and if you get one, you'll have to Bengal proof your house.