I'll tell you what, those cowlings may appear closed and secure, however they may not be.
I care not what they say, if I have to step on the sponson to check for the cowling to be securely closed, I may as well open it and check the oil level and the deck for debris loose items.
Same applies to the sliding xmsn fairing.
They could have made an extra effort for a sight gage or a flap door similar to the 412's one.