Klaassen was manifestly poor. Easily one of the most ineffective players I've ever seen in a blue shirt.Bolasie had a song about him
Can't remember a word uttered in support of Davy
So klassen wins
However... we shipped him out fairly sharpish, and got most of our money back. So, in the context of a thread called "Worst ever signing" where we are specifically asked to consider value for money, he's not the worst.
If we're talking about value for money we need to consider the fee paid, the amount of that recouped (or not), the wages "earned" and the level of performance delivered by said players. Bolasie, Tosun and Sigurdsson are the standout candidates, and the jury is out on Iwobi.