Originally Posted by albertogabbai
For infrequent flyers an important feature for the choice of the FF program is the non-expiration of miles. AZ miles currently don't expire, while AF/KL miles do expire. Also CO miles don't expire.
I would choose either AZ or CO.
If you fly once every 3 years, AF/KL miles will never expire. If you fly even less, why collect miles in the first place