I’ve done it both ways with/without vac bags. My personal preference is to use vac bags. The one time I did it without vacuum sealing the chubs I did get some water between the casing and meat. It could have just been the way I sealed the chub because I do know some people that just dump them in the water and have no issue. As far as taste goes I really didn’t see much of a difference between them. I’m sure more knowledgeable people then me will help you. Cheers!