It's used to be cheaper.
Factory used cast iron camshaft with a huge base circle, I mean huge.. and if you run too much spring.. and thats not hard to do... the core goes bye bye. They used the same old gear as they always did with that cast iron core.
Now billet roller? melonized gear is what I use and never look back. I'm a set it and forget it kinda guy, I hate having to check the bronze every other month... its easy, check the free play at the rotor.. but still.