from a personal experience, maybe avoid the drilled side of things and just opt for the grooved.
to many times ive seen cracks appearing in the discs around the drilled points, from where the disc heats and expands, then cools and reatracts and the hot spots take efect around this area and crack slightly.
it may not be an issue for eveyone, but one i have seen a good few times and enough to put me off drilled discs.