How about performing something that isn't done to death, or something that you know well enough that you don't get caught..
Or better yet, something that no-one has seen before!!
I agree with not doing something that you will get caught with. I garentee you that he wasn't the only one who knew how it was done, just the only who wasn't just going to be nice about it.
But I disagree about doing something that no one's seen before. I just don't do anything done on a TV special. Magician's might think that over done effects should not be performed, but it is really only other magicians who don't really like it. Most over done effects are "over done" because they are so effective or commercial. Effects that you perform should not be chosen on other magicians opinions of the effect, but instead the opinions of the spectators.
I think that there is no such thing as an over done trick to laymen, so there is nothing wrong with them.
As for the hecklers, you should try to play off them, add to a joke they make ect. Do not make fun of them or embarrass them, because they will just continue. You will be getting into a verbal fight with them and the rest of the spectators will not enjoy themselves.
Unless they are some punk magician, they should not be knowing how your tricks are done and be telling people. I chose better effects and practice them until they wont be able to know how it is done. If you make a mistake once and they say something, in my opinion, you should just ignore it and continue with a surefire effect. You should definitely not be making more than one big mistake for each persormance. You should actually not be making any.
Hecklers should be a sign to practice.