My very "best" Rengar game to date:
The game was a win, but the experience itself was a loss. I played with a 4-man premade team, therefore by default i was to blame for whenever they would start a team fight while i was clearing a minion wave so our team would get the money, not the tower (i never ignored them in favor of clearing the minions ... by the time i was half done they'd start their shit) or when they'd constantly overextend. Non stop flame from them drived me to the point of muting the entire team and just jumping at the enemy caitlyn during team fights and finishing off whoever wanted to retreat from the fight, not 1 player from their team tried to protect her.
Rengar feels strong, i built his items in this order machete>boots>madred>that 2 gold per minion kill sword>giant belt>wriggle>finished boots>frozen mallet>bloodthirster>atma>homeguard boots.
Next time i end up with a 4 man premade i'm dodging, i can't stand their shit anymore.