I like zipping mine out just to be sure I get the bones. I was at a buddy's house over the 4th for a fish fry and he does not zip needless to say I pulled a handful of bones out of my mouth through out the feast. I do however keep some of the smaller fish in full fillets for the grill or baking. It's a personal preference if you havnt zipped give it a shot and compare. I also skim all red meat and started bleeding my fish this year and I have noticed a difference in the fillets as well.