Used - removed when i did a wheel bearing a on an old g40 of mine a long time ago. Can't recall these making any untoward noises etc.
from reading forums i believe phil j can (could?) get replacement bearings anyway.
Help me clear the shed and have a punt at £15
Pete
(http://i90.photobucket.com/albums/k258/peteg40/20131128_220055_zps99972084.jpg)
These alot more durable than standard ones?
no idea!
the poly will probably be - unsure about bearings