I take it you do not have any problems with your set-up?! Leon is that A 3 or 4 row radiator?
So you can see in the link provided by Leon the difference between the two Fans. It sounds like Leon isnt having any issues. The set-up I had the problem with was using the the JWT radiator, Which I feel like would have been further away if anything compared to Leon Champion radiator.
Perhaps the problem is worn mounts, maybe worn blade too. And now with that fan sitting closer with the two former things mentioned Is causing it to hit.
My brothers car definitely had worn mounts at the time when we were dealing with this issue, which weren't replaced until after changing to the earlier style fan. But changing the unit to the early fan style solved the problem for us. Maybe new mounts could have prevented it too though... Good Idea to replace your mounts either if they are worn!