I dont usually post in this forum, but oh well.
Here are answers to your questions in order :
- The only difference you'll notice is that they are bigger, and just a slight bit thicker. I'm only saying this because you say your so 'use' to quarters, and you'll notice the difference. Normally most of the sleights done with a half dollar can be done with a quarter and vice versa.
- Theres no need to have spectators examine your coins anyway. Coins are objects people relate to. And plus a laymen doesnt know something called a shell even exists. But if you must, lets say you have 4 coins and the fourth has the shell on it, and you have 3 spectators. Hand out the 3 normal coins and keep the last one on your self. If you have more spectators, then dont let anybody examine it. Just go with the circumstances.
- I think getting them from a bank (supposing you live in the US) would be cheaper, you'd be getting your money's worth.
- It wont be considerably harder switching from quarters to half dollars. It'll just be something new, a bit awkward at first, you'll get use to it in a about 3 days practice.
- I dont think this is exposure, and Im too lazy to PM anyway. Think of a shell as half a coin hollowed own. It is what it is, a shell
that covers up another coin to make it seem as if there is only one coin.
- No they are not magnetic.
- An example effect of a shell would be that the magician takes one coin and splits it into two, puts one down on the table and splits it again in two, placing this one on the table and splitting it again, producing 4 coins. (just off the top of my head) You are not limited to splitting. There are hundred of effects using shells. Look into David Roth...Michael Paul has an interesting take on the shell and its uses...uhh I know theres a lot more. If genuinley interested in some resources about shells let me know, and I'll find some real good ones for you. No point in me naming for no reason plus...yeah I'm lazy.
I keep saying I'm lazy yet I keep typing. I guess I felt sorry for you as nobody replied...I take that back, I literally just loooked at the time stamp and you posted this about 15 minutes ago. I never type this much.