I've been using a Baofeng UV-B5 daily for over a year with a mag mount and external speaker mic with no issues and have 2 of them programmed identically.
Deal Extreme sells a Kenwood brand mic for less then $10 which ships directly from China,
http://www.dx.com/p/kenwood-kmc-17-heavy-duty-speaker-micphone-w-earphone-jack-106859. The baofeng external speaker mics sound like crap, and you can instantly pick out someone using one. Not that it's a drawback, it's still intelligible, I just prefer the cleaner modulation.
As far as buying Chinese, they're using the equivalent of slave labor, but that's a moral argument that goes beyond the scope of this discussion. Who is John Galt?
Regarding cross band repeat and a quad copter, that might be a little noisy. Why not a lighter than air balloon tethered to the ground? A light blue or grey color would be hard to spot. On a low duty cycle, it would last as long as the batteries. In fact, it's not a bad way to run an antenna. Cool idea, Gill. I was thinking through how to keep a balloon aloft, and how much temperature differential and volume would be required to use air only, or how to seal Helium semi permanently. I don't know if anyone's seen the balloons the feds use around FL. I'm pretty sure they're helium. Anyway... thanks for the discussion, as always. 73's.