Practising last night for my terrifying attempt at a solo gig (scream) with the creature known as the Fi, everything was running smoothly until an attempted cover version. Being British, we didn't say exactly what we thought. I could tell Fi wasn't too keen, but I insisted. Eventually she offered the opinion that "we don't want it to sound like a bad karaoke version of the song". Even I could tell that meant something not particularly good.
In the more objective light of the next day, I think she may have been right, and I think I may drop that cover. But, it made me ponder over when to go with what you think, and when to listen to others. Ultimately, there's no easy answer. It probably is a valuable exercise to try and curtail your ego, and to do what's best for the song/set. On the other hand, without the prompting of that ego, you'd probably have never got up on stage in the first place.
I'm not talking about standing up and shouting "Look at me! I'm the best musician you've ever seen!". Just by being on that stage however, you are saying that you think you have something to offer, something slightly different, something interesting, something curious, a new twist, some energy. Would the Beatles have been the same without John Lennon's ego? Without Paul's? Not really much of a Sex Pistols without an ego going on. No Hendrix, no Who, no Public Enemy, no Kinks. So, we have it to thank for some great music.
The hard part is knowing when your ego is being a twat.