Impromptu jungling is the best!! Play whoever you like to-- jungling is all about how you can use the champion. If you can play a nasty Jinx jungle-- go for it. Having a pinch extra dps at that level isn't too bad. Go in thinking what items are good on most ranged dps-- get a little armor--dash of hp-- then just keep plugging at your normal method. Hell I've been using Yasuo to jungle when I get the chance and it is really good. Jinx might not be the "best" because her kit isn't suited to jungle. "But" outside the jungle in the late game it is like having a second person to fight in the back line.