Matt and I have finished recording backing tracks on 16 original songs and 5 covers with drums, bass, keyboards and electric guitar to use in our live performances. Matt gets almost all of the credit as he played all of the backing tracks and recorded them. I listened, reviewed, made some slight suggestions, but mostly said "that sounds really good".
I was not sure about using backing tracks live but they sound so good and add so much that they cannot be denied. We are still playing and singing live too so the backing tracks add extra layers of sound. The drum tracks are super important as they drive the song. And it takes a lot of pressure off of me. When playing without backing tracks, each guitar chord and lick carries the song (sound and rhythm). With the backing tracks, I can relax more.
We are using these tracks already and our sound is pretty big for just 2 guys.