Dont buy chips like these "blizzard compatible" if they dont have the word blizzard or amiga in the name they are ten times cheaper .. The seller bought a LOT and sells them at an extreme price. I bought a Lot and sold each stick for about 2£ more than i payed for each . I have also had many different sticks some are not good for the blizzards others are..
EDIT
Why would anyone need more than 64mb with an amiga anyways ? Asuming they are not running os4 classic or morph ...