Calendyr
Hum... I just re-read the reviews for Gemaco... Nothing great.
I would still go with Kem over any other type of card.
Modiano also makes good quality cards now (Plastic Acetate), so that would be an option too. All I know is that at my club, Kem cards last 10 times longer than Copag cards, and for the price difference, that is a huge saving.