No. The drawback with cards like
Vexing Devil is that they give your opponent the choice. When you need a relevant 4/3 beater to even out the battlefield, he'll take the 4 damage. When you need that last 4 damage to close out the game, he'll let you have a 4/3 body that can't get through his blockers.
Most people who look at this card and think that it's OP (including me at first,) make the mistake of looking at the win-more situation. If you're already winning and control the battlefiled, 4 extra damage is great! So is another great beater! But in all the rest of the situations (you're both establishing the board position (early game), the board is locked down (tie) or you're loosing) the card let's your opponent decide what benefits you least. Example: If you're down on board position, the opponent will take 4, which doesn't matter because you can't deal enough other damage to close out, and all you really need is another blocker.
TL;DR This card is actually pretty weak, by letting the opponent choose the mode, you get the WORST of both worlds, not the best.
Sidenote, if it was:
R, Creature - Devil, When ~ ETB you may have it deal 4 damage to target player, if you do, sacrifice it. 4/3
THAT would be OP. It would probably have to cost at least 3 to even be considered, and it would still be OP. As a reasonably costed Rare, that would be 3RR, see
lava axe and
borderland minotaurAlso, go ahead and use our forums poll option next time, no need to send people off to a secondary website.