those pics above are some sweet rides.
My only experience with steel boats is working on my friend's older steel hulled houseboat. It's not that you worry about it rusting through from the outside, but they rust through from the inside in hard to reach places. You need to religiously check the anodes and stay on top of any rust ASAP. Good chance that if you find a used one, the owner will be looking to get rid of it because the rust is getting out of control, and will try to hide the worst spots.
If you do find one get a surveyor with steel boat experience.
IMO an aluminum hulled sailboat would be the bees knees. Still electrolysis is a major problem on aluminum boats, but I think making sure the bottom is painted and touched up is what you worry about and not that it'll rust from the inside out.
Back to houseboats on fresh water, most boatyards won't touch a steel hulled one because their hulls get real thin in spots and can't support their weight on the slings when they get pulled out. Owners are reluctant to let you take it out of the water for survey because of that, and so will you when it comes time for you to sell and get a bigger one(there will come a time).
Pro's....sweet boat, unique, strudy, seaworthy
Con's...expensive, more difficult to maintain, very hard to finance(if you need to), insure, and triple hard to sell, oh and Rust Never Sleeps.
By the way, just finished "Cape Horn to Starboard" about a guy who sailed around Cape Horn against the prevailing winds in a Contessa 32 and it was a great read. A Contessa 32 might be right up your alley too!