I use a double edged safety razor and have around a thousand blades, which cost about $0.02 per blade. I've always thought that disposable razor blades were an outrageous racket. Also DE safety razors make for a much smoother shave!
The price of cartridge razors also comes way down after you realize that, as long as you keep the blades dry so that they don't corrode, you can make 'em last forever. I think my record is something like 4 months on a single cartridge.
I read all of the DE blade shaving guides, but it really didn't work well for me.
All in all, they're definitely cheaper... But I don't know about better.