His win rate mainly stems from his incredible variety in hat you can build for him. Once people learn how to build him properly, I think his win rate will drastically improve to at least 52%. For example...
This is a good item on Kled right? Not really. Besides taking advantage of his high base health, it doesn't benefit Kled as much as other items do. Kled can use it, but it should definitely not be used as much as it is.
Not many people build this on Kled, but you know what? It's really good. It keeps them in range for his Q and drastically improves his stickiness so he can get all 4 of his W hits off.
Please, please get this on Kled, especially early game. Kled benefits a TON from Life Steal in the early game since it allows him to rejuvenate damage dealt to Skaarl and therefore perform better against poke and in trades. Death's Dance is better on Kled than other Life Steal options since it provides him CDR and added defensive stats.
Ok ok, this can be good on Kled, but there are better options again. Definitely buy this if the enemy team is getting Armor items and a decent bit of Armor items at that, but otherwise please buy another Armor Pen item over this. As Kled, you want to be focusing squishies first so getting flat armor penetration is a ton better than % armor penetration. The attack damage and CDR is great all, but it still isn't better than getting this over other items with much more synergy in their passives and actives with Kled.