Always a peeler. Always always always. Because it's the correct tool for the job. Knifes are for slicing, dicing and chopping, peelers are for peeling (the clue's in the name!). I have different peelers for different kinds of food :)
My aunt gave us a COMPLETE Kenwood Chef with ALL attachments as a Wedding Present, & one of those was the 'Potato Cleaner'.
It was a bowl with 'sandpaper' sides. You'd add a little amount of water, spuds as required for meal, set it going, & 'sandpaper' would remove skins so evenly!
Waste then put on garden!
Vee you took the written word from me! A peeler takes off less potato, I think, that a peeler, & I find a peeler is a lot quicker to use. Some sorts of potatoes I don't have to peel, which is even better.
miro_, oh, I bought the best peeler I have ever used just the other day. I bought a Jamie Oliver one you can find at Woolworths. I thought $8 was a bit much to pay for a peeler, but it was truly worth it. It takes off just the skin, and it glides. Oh, how it glides! Who thought one could get so excited about a peeler! LOL.
I have found a photo of my beloved peeler. This one (pictured) has not been treated well. Mine looks almost the same as the day I bought it. I would really be lost without it as it is the only one that has ever suited me.