Those insulated fish bags are only as good as your ability to keep ice up to them .
They were designed for oversize fish like tuna / mackerel where you go out for the day , catch your fish - put it in the bag which is full of ice ( 2,3,4 bags) & head home - It just allows you to keep the fish cool & hydrated rather than having it sit on a deck in the sun for a day - they are a revelation though as some are up to 2m long .
They work & do a job but dont compare to a typical insulated esky ....... that said , they are foldable & can be kept out of the way problem is where is your ice being stored ?
One thing is that fish spines can & do puncture them .
I thought about buying a 150cm Chiller bag but ended up just going with a bigger 158lt mackerel box ......
Chris
PS - Brett If that was my boat - I would redesign the skippers chair to allow a large split lid ice box to be slid into place (260 lt IceyTek)