One of the first Nacra F18 nationals was an open event to the Tigers...subsequent events were closed. I can sorta see why it might be closed event (since it's the "Nacra" nationals and all)...but then again, if the manufacturer is fully embracing F18, perhaps an open event makes sense. Regardless, if it comes to decide one over the other, there's no way I'm missing the North American F18 Championships in Lake Carlyle. I think the affect on events might be that the F18 North American's will draw attendence from Nacra NA's...not the other way around.