As the inventor of the Brown Hornet, let me answer a few of the above questions.
It's very important to not have a direct link between the clipboard and yourself. Here's how most people do it: They hand someone the clipboard, have them write something while they hover nearby, then immediately take it back. Of course an audience participant is going to get suspicious. The secret is to BREAK THIS CHAIN.
I usually let an audience member take it around for people to write on, then she brings it back and puts it away in my case while I talk to the audience about my premise. I get the peek -- which takes about a second -- when I go over to retrieve my sketchpad and pen. I also have a peek in full view of the audience, which uses a book as a cover.
100%? Hmm ... what is? I've occasionally performed center tears or billet switches, and had the ORIGINAL writing to look at -- and couldn't read it! I'd say the Hornet, and its little brother the Skeeter, is more reliable than even the legendary Nelson Ultra-Perfect Boards, which used to let me down on an occasional basis.
The Hornet captures writing as well as drawings. Clone Pad, Kopy Cat, and Buma do not capture writig as well, but are great for design dupe.
To increase the likelihood of grabbing legible writing, I always try to tag a large, extroverted person. The principles of Graphology state that such a person will write big and bold. And they almost always do.
If you want to check it out, go to my website of secret STUFF at www.jonsaintgermain.com/books.htm
You have to access it through this link; the pages aren't accessable through my main portal.
I invented the Hornet, as I've done all my stuff, with ME in mind. I was tired of buying props and throwing them away as soon as I tried them out. It's a professional device intended for serious performers with some experience performing for real audiences. I made something that I would use, raod tested it to death, improved it, and them began making them for my friends.
I make them by hand, and am glad to make them in limited numbers for serious chaps. But be aware that I perform for a living, I'm away a lot, and I don't mass-market any of my stuff. So you might have to wait a couple of weeks if you order something. Also, if you're into debunking or sympathetic to skeptic groups, CSICOP, Randi, Shermer or Mark Edward, please do me the courtesy of not trying to buy anything from me.
I hope this helps, and e-mail me at firstname.lastname@example.org
if you have questions.