In case anyone is interested in hearing more about the E-Werk as I continue to experiment with it, I've started a blog entry about it.:
http://hpscott.wordpress.com/2010/06/10/ewerk/
I continue to be very impressed with it. As mentioned above, I don't have an iPhone, but the E-Werk causes my cheapo prepaid phone to indicate that it is charging by just a few miles per hour.
I definitely wouldn't argue that the E-Werk is an economical solution, but if, like me, you get a kick out of the "elegance" of not buying batteries or needing outlets while on tour, I think this is a good way to go.
I still don't have my iPad yet... should be here end of next week. I'm very curious to see if I'll be able to charge it directly from the E-Werk. If so, I think I'll be all set.
The real test, however, won't start until my tour (July 8th), but I'll keep the blog updated as I go.