I'm looking for a good external power solution for an upcoming live event.

I've already got the dcc8, and removed the original adapter to solder on a more standard sized connector (radio shack, size M DC plug) so that I could plug in the plethora of 9v 2A wall warts I already had. But I need to be able to shoot for hours at this event without being near a wall plug. What do you guys think are my best options (without breaking the bank)?

Someone mentioned the Tekkeon Mp3450i: http://www.bhphotovideo.com/c/product/618847-REG/Tekkeon_MP3450I_myPower_ALL_Plus_MP3450i.html/ but at $140, it seems kind of pricey to me. I feel like once I've gone so DIY this far, I should be able to do this for less than $80, right? I've seen those cctv batteries from china, but ordering from China takes too long to ship (shoot is in 2 weeks, shipping from china generally takes 3-4 where I live).

Some options I've been considering: http://www.amazon.com/15000mAh-External-Motorola-Portable-eletronics/dp/B0067XMPNY/ref=pd_ybh_14 This one looks interesting- has an LCD display. Not sure if that doubles as a battery life indicator, but the price is nice.

http://www.amazon.com/EZOPower-High-capacity-Rechargable-10000mAh-Blackberry/dp/B005XQSN9G/ref=pd_ybh_11 I like this one simply because it is Amazon Prime compatible and has some reviews. Its less capacity than the previous option, which had 50% more than this.

Then there's the whole RC battery thing... I have no idea where to even start with those! I've seen some folks post about how great they work, 8+ hours, etc- And videos like this one:

But then I hear rumors about how when these unregulated RC batteries are are first charged, they peak at more capacity than they are rated for (some close to 10+ Volts, even approaching 11 according to someone's volt meter), and how folks have fried their GH2's power chip using them. This makes me nervous. But some folks have claimed great results with this, so...

I'm looking for any kind of advice/guidance at this point. Thanks!