I have a dyno port mid top pipe.  It fits perfect with the stock plastics but it doesn't seem to perform very well.  I put a FMF pipe on the same quad and it woke it right up.  Pulls the front tires from what seems like idle. It doesn't rev out real high but I prefer this pipe in the trails compared to my HPR pipe.  No cutting of the fenders and they are cheap and plentiful.