The Aero halyard doesn't flap if you rig properly.
Those who sail in sandy places may not be too keen on zippers.
Plenty complain about the difficulty of rigging the sleeved Laser in big breeze and adding full-length battens is going to double that pain.
Don't get me wrong, I love the Aero. But my main complaint (which really isn't a complaint b/c there's an easy workaround) is that the halyard pops off the cleat on hard, smashing capsizes (even if you don't pole-vault the mast on the ground beneath the water). Again, not really a "complaint" because I just shackle the head of the sail to the top of the mast and all is well. But there are some reasons to prefer a sleeved sail over a halyard.
On my Sabre (Aussie class) with a halyard most boats either have a v-cleat or a horn cleat and never pop out that I know of.
Is the cleat at the tip of the mast, or at the base of the mast in the boats you mentioned? In the Aero, the halyard cleat is at the tip of the mast. So, if you have a really really hard capsize in heavy surf (which happens to me a lot, but is probably not a concern for most Aero sailors) that cleated halyard swings down like a baseball bat at the tip of the mast and slaps the water REALLY hard, and then gets throshed all around in the surf. If the halyard cleat is at the base of the mast, then the cleat is probably immune to this kind of throttling. But with the cleat out at the end of the mast, my personal experience is that this throttling at the tip of the mast knocks the halyard out of the cleat.
TO ANYONE INTERESTED IN THE AERO - this is not a big deal. If you're not routinely having lots of really really hard capsizes in big winds and surf that slap the mast down into the water really violently, then this is not going to happen to you. And if you *DO* do that kind of sailing w/ the Aero, then a shackle solves all the problems. But that being said, if I ever do buy a Melges 14 I'm going to trash it in the surf, for which it will be nice to have the sleeved sail.