The aluminum filters work very well, just good as the plastic fiber, and I think that they'll last longer. It's easy to pop them off and wash them. You can screw them onto the fans, or directly to the case.
I think it's better to attach them to the fans. If you examine the areas around the fan holders carefully, you'll notice a slight problem with finding enough metal for drilling extra holes for the screws. There's already too many holes in the chassis ... hence the fan holders.
The filters <i>are</i> slightly larger than the fans, even though the screw holes match up, so if you want to connect one to a fan, and then place it in one of the fan holders that come with the Antec case, you'll need to take a dremel tool and cut them down to size. It's not difficult, and the metal is fairly pliable, but you should be aware of this. I once trimmed 16 of them in a day ... and boy, they get hot when the blade on the dermel starts cutting! Wear gloves.
But I figure it's worth it ... they'll last damn near forever.
Here's a good, reliable site for ordering them:
<A HREF="http://www.2cooltek.com/" target="_new">http://www.2cooltek.com/</A>
As for the fans ... ball-bearing are considered to be better than sleeveless, and will last longer, but are louder. Beyond that, I've never seen much difference, unless the fan has a higher RPM.
Toejam31
<font color=red>My Rig:</font color=red> <A HREF="http://www.anandtech.com/mysystemrig.html?rigid=6847" target="_new">http://www.anandtech.com/mysystemrig.html?rigid=6847</A>
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<font color=purple>"Have you noticed how much they look like orchids? Lovely!"</font color=purple>