Originally Posted by Fat M. Rock
Murkrow is pretty situational, and it's not terrilby easy to use. It does not last as long as you'd think, and it needs teammates that can help take out what troubles it.
I've tested Murkrow extensively, and have to agree with this for the most part. If you want to use it, you need to take advantage of its unique niche: being basically the only viable user of Quash (and Prankster Mirror Move, to a lesser extent, which is really situational but lets you do some useful things like reversing Trick Room). While its bulk doesn't compare to the other viable Eviolite users, it's not terrible either - 252/252 Calm will always survive Latios's Dragon Gem Draco Meteor, for instance.
As for the others: Porygon2 is sort of a jack of all trades, capable of doing a lot of things but not excelling at any of them. Dusclops is an excellent supporter, plays very similar to Cresselia. Chansey can't really do anything in doubles outside of Guard Split or Minimize shenanigans, and I haven't heard anything about Lileep so I'm not sure what's up with that.