The Image Cache you referenced is not specific to Pure. It is a common Cinder feature that many backend can leverage.
You can use both the image cache and cinder as a glance store as well but they are redundant. It is best to pick one or the other.
It depends on the images format you are using. For example if you are using QCOW2 as the format the glance cinder backend cannot optimize it, but the image cache can optimize.
Simon