I occasionally shave off the 6k to test the edge but as mentioned above for a smooth shave you really want a little more.

Depends on what you are planning to hone. If you want to keep shave ready razors in tip top condition I wouldn't bother with it but if you want to revive rather sad looking blades on the cheap and aren't in a rush it does the job. If you're hunting the bay for a cheap honing solution a King combo along with a natural finisher like the Chinese 12k should provide a decent edge, maybe a touch of chromium oxide on a strop for a little extra zing.

It's a cheap work horse that keeps everything in the house sharp. For the price I look upon it as a 1K stone with a freebie on the back - a bit like buying a coticule with a belgian blue on the back.