when you said "really good" that limited suggestions. Then on a 300 RUM my next tho't was "for what use".
Really good for ruggedness: SuperSniper 10X or 16X
Really go for hunting: Elk hunting-not a 16X SuperSniper, maybe a 10X Lack of variable power will probably getcha. Though would be great for full daylight shooting.
Best of all worlds. IOR, USO, NXS, Zeiss (Conquest or Victory), Leuy LRTs, and others.
Then there's the S&Bs that Boss Hoss mentioned. Can't go wrong with them.
I may be the slowest guy on the mountain . . . . but . . . . I'm on the mountain!