I would go with the Screwdriver, only because Trog has been building them for awhile and has a good support network built up around his product.
The button may not be in the best possible place, but you know this device is going to produce some vapor.
I have seen video reviews of both the GG and the Silver Bullet. To me they are not that impressive. The Prodigy is known for burning up attys @ 6V, the GG produces about as much vapor as a 510 on a good day, and the Silver bullet I'm not too sure about, it is still too new.
BTW, I really like the idea of you suc.......nevermind
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Cigarette free since May 4, 2009, and hoping to vape longer than I smoked

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