Let me begin by saying, forgive me, but I'm a bit of a soap snob.

Most (usually all) of the soaps on drug store, supermarket and mega mart shelves are not true soaps but rather detergents. Look at the ingrediants for your bar soaps, hand soaps, body washes, shampoos even toothpaste. They usually contain some form of sodium laureth sulfate. Even the high-end stuff. That chemical is a degreaser and a foaming agent. Remember "Zestfully clean?" The reason it left no residue in the shower and rinsed clean off your skin, so your skin felt squeaky clean, is because it is made mostly of cheap detergent. The degreaser strips all the oils off your skin. Trouble is your skin needs oils to be healthy. That and there is much discussion and debate going on as to the safety of using those chemicals (and the chemicals used in fragrances) on the skin, because by applying them to the skin, they are absorbed into the body. But thats another thread.

So a good soap will clean off the dirty oils from your skin, but will leave behind clean, healthy oils to replenish/moisturize your skin. I make my own soap (real soap) and have for years now. My recipe does just that. Cleans but leaves behind oils to make your skin soft and nourished, even in winter when the skin on my hands would normally crack and bleed and my knees and elbows would get all flaky and itchy. I have also found that the oils in my soap make for a nice slick shave and don't dry out my face either.

So having said all of that, I'm not sure how well a standard soap will perform as a shave soap. If it is slick enough, it may dry out your face if you don't treat it with something else like a heavier aftershave lotion or something. But the only way to find out is to try it. As for the foam in a can, well in addition to my rant about chemicals, I agree with what has been said already about losing a part of the straight razor experience if you go that route.

my 10 cents worth