ok guys so i'll try to make it as short as possible,on those days i'm trying to play this champ top and i can't deny i find it funny and also challenging.
You have some sick damages with DH and you can counter most of the top laners, usually i find my self behind on minions because i like to roam a lot with Karma is so easy to pull out a easy gank thanks to your E+W, and minions are not a problem if you are 4-0 right ;) ?

The biggest problem of this champ is how fragile this champ actually is , you can be full hp and get shut down in less than 0,5 so positioning is a required skill , also always because you are fragile + you don't have many ways to run away from gank you need to be really aware of enemy jungler.. if he's smart he'll probably gank top lev 3 or maybe 6 in case of champ like Rengar,Eve,Noc so be careful if you fall behind is a problem !!!

Good fact about this champ is his ridiculous early level damage, seriously is something insane.. so just q the first 3 minions so you are sure to actually don't push the lane then asap hit R+Q and check the output damages ( care on minions aggro they actually can hurt you really bad ) by the way you don't need to actually get 10 kill in 10 min to be big, be sure to make your enemy top/mid laner to fall behind and farm the DH stacks you need them for the one shot :P