What is your favorite Strauss The Last Four Songs?

I've enjoyed Norman with Masur for a long time.

Also Schwarzkopf-Szell.

Another winner is the more recent Isokoski-Janowski recording suggested by Dave.

A clear winner for me is Gundula Janowitz with Von Karajan conducting.

One that I am also attached to is Jessye Norman with Kurt Massur conducting.

There are also a good number of others that I like in certain songs in the set but not all four. 

My satisfaction for the two named are because I can find nothing to criticize in them.

Felicity Lott, an unlikely recommendation, and Jessie Norman are my go tos