It really depends on what kind of paint you used, how well you prepped the hull and how good you were about repairing any scratches or damage to the paint.
To give you an idea of what the difference can be, look at some commercial fishing trawlers... most are steel hulled, and often the front half looks almost pristine and newly painted, and the rear half looks like a totally different boat, with big rusting patches and such. That's because dragging the fishing gear over the side damages the paint job and the steel hulls rust much faster in the rear end of the boat where the gear comes on and off.
Thanks SD it sounds like with proper procedures steel can be a very durable material free of blistering for sure
I will see how it all plays out as far as this boat I have been offered in a trade for my home.