<< hi ugh,
i'm not positive, but i don't believe that they're really comparing the same things. i'm lead to believe this because the L1A panaflows that i purchased are listed as "brushless" and "ball bearing." generally speaking, most fans are either ball bearing or sleeve bearing. in general, ball bearing are better than sleeve bearing fans.
i know this doesn't really answer ur question, but i hope this helps some.
lordbob99 >>
Ball Bearing better than Sleeve Bearing?
They each have their own advantages and disadvantages. Ball Bearings have less resistance and will last longer so they are more dependable, Sleeve Bearings tend to be a bit more quieter than the ball bearing since there is no vibrations from balls. Reason why the Papst 8412NGL fans are super quiet! They're even quieter than the panaflo L1As which are ball bearings I believe.