Not sure what a "DB" is. Double-edge? Anyway, I find that if I use a brush and soap & prep well, I can even get a decent shave out of a multibladed disposable cartridge, and a faster one: a single pass with the disposable is much closer than a single pass with the str8. But I only get two decent shaves. After that, my barbwire beard starts eating the edge. For me, the magic of a str8 is the ability to touch it up with a pasted strop, thus giving a perfect shave every time.

Not all men have this problem. My buddy Sam says that the same cartridge that lasts me 2 shaves, lasts him a whole month. His beard is softer. For him, maybe the hassle of a str8 isn't worth it. But for me, it is.

I suppose I could buy a crate of double-edge blades on ebay & chuck each blade after 2 shaves, but that seems wasteful & aesthetically displeasing. At least to me.