I agree that the best thing to do is be ready to adapt. I have almost all of my rigs pre-tied, but if I run out, I can tie a new one right onto my topshot very quickly with just the supplies I keep in my pockets. Just tie up a surgeon's loop and two droppers, and you'll be good to go pretty fast

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Last trip I was on, we had more of the "fun size" models, so 2/0's were better. If you had a 4/0, you wouldn't have had such a nice catch by the end of the day. Even the cod there were fine of the 2/0's (at least mine was- I had a 21 incher). I think that the 2/0 is a nice size for almost all bottom fish, even porgies. They have always been fine with me for almost all of my fishing.
Have those rigs ready!
Ryan