I have only seen a few sets of All Balls bearings but no, they are not the quality part that you would get from a regular bearing mfg. or OEM. They are working fine in my steering head but that is a very low speed use although wheel bearings are also relatively low speed.
You can save a few dollars and still get the same quality by buying the bearings at a bearing supply house. Bearings are normally standard sizes as are seals and any bearing house will be able to get them even if they do not have them in stock. Unfortunately the Kawasaki part number won't work and you will need the actual bearing measurement. A larger bearing house will match the bearing(s) and seal(s) you bring them though so as long as you can wait a few days that might be a good option.
Brian
I am replacing the wheel bearings on my C14 since I am taking them out to get the wheels powdercoated. I will probably get OEM bearings, but wanted to make sure that All Balls bearings weren't just as good. They are cheaper but if they aren't built as well I will probably just go ahead and pay a little more for the Kwak bearings.