Those are some very good points. I keep a spare handheld GPS in the bag and have paper charts for all the areas I boat in but have been caught out in the fog with no radar. I have seen some rigs with a single radar pole bolted to the deck and supported by the grab rail. I can't imagine this setup would be too much of a hindrance on casting. I believe the units on the market today still run in the $4K-$6K range which I would consider a substantial investment for a 20' center but to your point how much is your life worth. I hope that boats without radar use good judgement when moving in the fog and reduce their speed to what is reasonable for the given visability but realize that may not be the case. I took a navigation course run by the Power Squadron that I thought was pretty good. They ran it as an option after the basic boating course. It was about 10hrs in total meeting once a week for a month.