Im pretty sure 2 Gig is the max. Replace batteries often, and if its really hot (or cold) use lithium batteries.

Fix mount it, dont hand hold unless you really concentrate on keeping it steady. Usually with a roll of electrical tape you can mount it about anywhere.

I wont be at SF as were going to Virgin Islands to film superstars JC and Trey, but Ive got a couple new Hero3's left, if you want want send be a PM and Ill make you a deal.