iPhone Users and external batteries

[LD92599]

Does anyone use an extra battery w/ their iphone and if so, which one? I've always used a Mophie Juice Pack but since I upgraded to 3GS the Juice Pack doesn't later more than an hour, whereas w/ the 3G i'd get at least 3-5 hours if not more. I'm lucky now to get 10 minutes from it!

Mophie already replaced it 3 times and it's the same issue; Apple replaced the phone too and it's the same issues.

What else is out there?

[jenmcadams]

We got the 3GJuice from Amazon and it works great:

http://www.amazon.com/3GJuice-2-0-DeLuxe-Version-Battery/dp/B001DDYH9I/ref=sr_1_1?ie=UTF8&s=wireless&qid=1262733749&sr=8-1

Edited to Add: We primarily use it on long trips and have used it with my DH's 3GS and with my 3G