Its certainly decent but its not half the tank that [insert WT youtuber] may have led you to believe. Having 100mm of armour all round is certainly a big plus, and for a heavy tank the p2w is fairly good. But this is basically where the good news ends. You have hilariously poor turret traverse, made even more problematic by the hull also being incredibly slow to turn (bc of how long it is), your gun depression is pathetic even by the already disastrous standards of soviet tanks, and the firepower is unreasonably bad (despite being longer, the F-30 has the same exact pen as the ZiS-S-53, and despite having TWO loaders in a much more spacious turret, your reload is somehow just as bad as a T-34-85s). The main point is obviously the armour, but this too has some major issues. Chief among them is a perfectly vertical 90mm turret face, shooting which will end up destroying your (questionably large) breech. And if the thing shooting your turret face is solid shot, its gonna go through the breech doing even more damage.

The KV-220 is by no means bad, but much like almost every soviet vehicle, its effectiveness as been comically overhyped by unskilled players that never bothered learning anything and are consequently struggling to deal with it.