I think that everything has it's time and place. For example, if you have a real heckler who's burning you're hands like mad, why not take out a gimmick to just destroy him. But there are many advantages to regular cards as apposed to gimmicks.

First of all, you will have to carry around a lot of stuff while using gimmicks, which can be messy.
Secondly, it's just not clean. Spectator often want to check the cards and such, gimmicks sometimes does not allow that.

But then again, gimmick can provide what sleight of hand cannot. Though personally, I have a few gaff cards, but sleight of hand can never be replaced.

Sick! Pitt Hartling! Well, hope to see some more magic videos soon!

I GOT IT! IT"S HERE! =D

Everyone has thier days, and that day was not his day. He got what he deserved.

Sounds like a great idea. I would say crimping and allowing the spectator to shuffle is the best way. Also, simply holding a break longer than, do the pass or control will be more convince as appose to right when the card is returned to the deck. This way, people will loosen up.