The difference between the Loyak and the Loyak AC is that the upper of the Loyak is a hydrophobic canvas and the AC is a ripstop mesh. Additionally, the Loyak AC comes with a 7mm EVA closed cell foam footbed.
The Danner Rivercomber looks like a pretty awesome water shoe as well. While we don't carry so we don't have any personal experience, it is based off of their popular running shoe model the Trailcomber. As such, it would seem like the Danner was designed a bit more for performance on the trail compared to the Loyaks.
Hopefully this helps, thanks!
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