pilot bushing

I am putting a new clutch in my 02 f150 with the 4.2 in it and looking at parts I see pilot bushings and also pilot bearings. From what I understand they are interchangeable parts and you can use either of them right?
What is the difference between the two? I am assuming a bearing has to be better than a bushing but I don't understand why the bushings are so much more expensive if they are an inferior product. The bushings are like 50 bucks and the bearings are only 15, but which one is actually the better alternative?

a bushing is solid and most are made of brass. the bearing is made of steel. steel is cheaper to buy than brass.both wear about the same.some people prefer the brass solid bushing,some prefer the steel bearing.i always went with the solid brass when i replaced one when changing a clutch pad.i think the main reason most people go with the brass bushing is it would be hell to put a bearing in and it be a bad bearing and they do sell bad bearings and have to go back in to replace it.the bearing should come pre-lubed and you will have to lube the bushing.