Not to bag on the site because I think it's useful and the author does walk people through a lot of fun and interesting upgrades, but a lot of the comparisons employ circular logic and just rehash marketing material. Something like...

1) The nice bike employs 7075 alloy aluminum in its frame.
2) The crap bike doesn't.
3) The nice bike is better because it employs 7075 alloy aluminum in its frame!