Bonus points for NsCDE window manager!
I have the cheapest Gilette, and am using it for a number of years now. Have used about 7 or 8 replacement blades.
My experience is that you only cut yourself when the blade starts to become blunt. So I try to replace the blade just before that :)
I only use some shaving cream (cheapest at the supermarket), and shave before I hit the shower, where the shaving cream is flushed away. No after shave or other stuff from the cosmetic industry.