Bushing or Bearing?

This is what I have in the car now

http://www.brewersperformance.com/proddetail.asp?prod=PB5300

Ive only put about 1,500 miles on it but I've heard that they can eat up the input shaft. Is this true? It fit the 318 crank so I don't see why one wouldn't fit the 340 crank. The bushing was simple but it seemed to work good from the factory, my a230 went 250k miles behind my slant six and it had a bushing. When I get this engine in the car I plan to put a lot of miles on it so I want something that's not going to give me any trouble. When I push in my clutch something starts to squeak and It drives me nuts, I don't know if it's the throwout bearing or the bearing in the crank but it makes me paranoid and I want to fix it. If it's the bearing in the crank that's squeakin then that makes me want to lean towards a bushing. Would the bearing be more reliable than the bushing? Or would it be more prone to breaking since there are more parts to it?