If you're in the game for status benefits, neither. Altitude requires Aeroplan membership, and I can't recommend that program. Check other Star Alliance programs.

The beauty of WestJet Rewards is that you can get partial rewards. You don't need to wait until you have enough points for an entire ticket. Yes, there are other perks, too, but not as good as, say, Star Alliance Gold.

At the end of the day, it depends on your travel pattern.