Personal preference is very important when deciding whether you want a knob or pull. Your hardware should be in keeping with the style of your kitchen, but it must be comfortable to use, too. Carefully check out the knobs or pulls you are thinking of buying. Place them against cabinetry, then see how they fit your hand. Are they the right size and shape for you?
Let’s talk first about metals. As a general rule, I like to keep the different metals in a kitchen to no more than two. If you have stainless steel appliances, that counts as one metal. So that leaves one other metal you can bring into a kitchen. If you’ve got brass light fixtures, that’s your one other metal. Your new hardware should be nickel or brass.