If the manufacturer recommends it then use it. I'm pretty sure they mean 6 percent table vinegar not commercial vinegar, with acetic acid solutions 5% to 18%. Call them and ASK THEM.

I have a black granite counter top, and for several years I lived with the calcification around the faucets because I was afraid to use anything. Finally, I cut a narrow strip of paper towel, dampened it with vinegar, wrapped it around the faucet and poured more vinegar on the strip. I kept the strip wet with vinegar and let it soak quite a while, and it all scrubbed off with a toothbrush. No damage to the granite.

Christie, I think you are asking about the finish on the faucet? I use regular white vinegar in a lot of my household cleaning without problems, but admittedly I don't have any brushed finishes.

Vinegar is a very mild acid which won't hurt the faucet finish. It also won't hurt certain dark granites like black or verde butterfly. However, don't use it on marble, travertine, limestone or light colored stones that contain calcite, because any acid at all will eat away at the calcite and cause permanent dulling.

Yes I was asking about the finish on the faucet. Thank you. I had tried just wiping off the sink with vinegar but it wasn't doing much. Letting it soak for awhile and then a little scrubbing did the trick. I used your paper towel suggestion Sheilajoyce. That was very helpful since there is a little groove around the top edge that's hard to clean. After I was done and has it all dried off, I rubbed some veggie oil around the faucet area where the deposits were the worst hoping that will make it easier to keep dry and clean.
It looks like new! Thanks so much for your help everyone.