I have flown into OSH many times with very few problems (other than the occasional idiot). This year we were sent to a left base 18 and the plane ahead of us was sent to a right base 27. Wind was not much of a factor. In my opinion (for what its worth) I think these this combination puts the planes in to close of a proximity. I was turning left at the same time he was turning right. Very close and made my passenger uneasy. Any one have any thoughts on this?