I know it's still too soon to call this, but both feel very underwhelming to play. Both are in about 43% win rate or less. I can't make them do "game changing" plays or win lanes with them. Probably Syndra needs a hotfix too.
Ulquiorra9952 votesVlad's only strenght currently seems to be not dying. He can survive fights... and that's it. His DPS is terrible and his team utility took a noticeable hit. Hell, even his sustain which is supposed to be THE strong point of his kit sucks as it is tied to huge delays.
Cassio... well, I like how they are focusing on making her revolve around their poisons. But why the hell does her Miasma have a minimum range? Would Riot's balance team just drop dead if they for once made a mage whom Zed can't kill and get away without reprecussions?
yeulx1 votesu know the definition of hotfix is to fix liek bugs with them ext. its not that they are underwhelming but riot said that they wanted the new mage reworks to fill niche styles of matches... like u only wanna pick cassiopeia if the enemy team has a ton of dashes and movement abilities....vlad.. hes ok but they changed it to where u want to use ur Q on an enemy champion instead of minions because when on a champion u get more hp
DJ S0NA1 votesBut she feels completely useless in teamfights if she misses her ult. If she hits Q and starts Twin Fanging, the damage is low. It was completely gutted from the old machine gun Cass. Previous Twin Fang was stronger than Poisoned Twin Fang now.
yeulx1 votesYes that may be true tho shes suppose to be a disruption mage now vsing those only niche types of champions with dashes... i mean just think when ur vsing team with dashes ur W will completely dominate them... shes not ment to be playing vsing high burst mages ext and but u also have to think of the cass before the machine gun cass.... not everyone liked machine gun cass or u would have seen her played alot more... personally i like cass.. and i even dislike the old casses playstyle because if u fked up just once with missing 1 Q ur basically screwed... think of it more or less like a power shift and hwo if ur target is poison her E does double damage on a 1 seccond cd..and now she also she can now get 6 ap items compaired to other mages... so i picture all cassiopeias should be building 
WitchQueen Annie1 votesI can confirm the new Vlad feels very VERY underwhelming. His E is impossibly hard to aim for very little pay off and his Q's damage has become a joke unless you hit the empowered ones.
His laning is fine but once he goes into team fight, his huge DPS nerf is very very noticeable.