Stick both tracks in a multitrack session and in Preferences>Multitrack, set track solo button so that it's 'exclusive'. When you hit the other track, the one you were previously listening to is automatically muted. You can put as many tracks in as you like this way, and quickly switch between any of them. I use this method for comparing takes quite often.
One of the big advantages of doing it this way is that you can also set the replay levels for each track independantly in the mixer - sometimes that's useful!