1% isn't much statistically. Even though it means that in each 100 you get 1, it's not like that, since the % isn't cumulative. However, it means that if you play an infinite number of games, you will get ("infinite")/100 cards. You can play 300 games and don't gain a single extra rare card, or you can play 50 and gain 3-4 extra rare cards. Theoretically, the more you play, the more the % will tend to 1%.
I got at least 1 rare card thanks to the Orb (I think):
Defend your territory. &
Tailored Suit.
Other than that, I don't think it gave me anything else.