User blog comment:JayfeatherXThestick/Attack speed Pantheon, why he might be viable./@comment-5038450-20140326171551/@comment-24557608-20140328200610

With back door plating it takes less then 30 seconds with 2.5 as.

Also Master Yi also can't take down tower quickly without a good supply of items as well as an AS Pantheon.

Rengar won't even have the ability to do that in the next patch or so, and he is item dependent as well. Unless the opponent is stupid enough to give you farm or kills as Rengar, taking down turrets is one of the only reliable jobs you can do, while AS Pantheon has the option to assassinate adcs as well as back door. As Pantheon, it is much easier to get kills in the early game with your poke and combos and is still able to get CS while doing so.

Rengar has to dedicate his whole early game to standing in the bush and jumping out of the bush if he even wants to get kills and snowball into the late game and there he can only get 1/10 the CS his opponent is getting.

Jungle Rengar isn't going to get the chance in the early game to snowball if the enemy puts one pink ward in the river or jungle while a jungle Pantheon could just jump over such a thing.