I think covers are great, especially at a live concert. Heart, who I was never particularly fond of, used to cover Zepp's "Rock & Roll" in concert regularly. Zeppelin used to do a medley of old blues songs and incorporate Elvis into "Whole Lotta Love" during its live performances. Springsteen, for years, played a great medley of songs "Devil with a Blue Dress/Jenny Take a Ride/CC Rider/Good Golly Miss Molly," and "Twist & Shout."

One of the best covers that I forgot in an earlier post is "People Get Ready" by Rod Stewart & Jeff Beck. The original artist escapes me at the moment.

Many of Elvis' early hits were covers.