Depends on the situation and enemy you're facing.
If you're fighting a full Asura Champ you'll need the Devis to survive, but if the champ uses TSS you'll die fast on Devis so you need to switch cloaks. You'll need to switch cloaks often anyways since most classes use a Thana weapon and a non-Thana weapon to counter Skolls.
I'd recommend having 3 cloaks:
First with 2 Skolls
Second with 2 Raydrics
Third with 2 Devis