I was wondering what nihm receiver pack would be good for my Extra 300 running 7 Hitec HS-5985MG servo's. I am also interested in a redundant setup, and would like to know everything involved and how to set it up. Does this setup require 2 receivers?

A123 cells without a doubt.

Heaps of current capability, plenty of voltage head-room.

yea, ive seen those and they do look very nice, but im not ready to switch to lipo yet. My charger only charges nimh.

im no expert but i would say 2 2500 ma batteries, 2 separate switches and 2 plugs into the receiver. back up is done and when both running 5000ma worth of battery is heaps

Elite 1500's from Hangtime hobbies. Should get you 4-6 10 minute flights depending on how you fly and what size airplane we are talking about. These are good little batteries, low impedance so very little voltage drop under load. If you think you need a little more power, go with the Elite 2000

Myself and most people I know use 2 batteries into 2 switches into 1 receiver. 2 receivers is not required

http://www.hangtimes.com/giantrxpacks.html

you have to consider the weight your putting in the plane with redundant nimh's.
get a setup from duralite, or go a123's(prefer a123, no voltage reg's).

A123 is the future... If you can use them..
Tom at WildHare has a starter package around $150 with 2300 battery,
CellPro charger SUPER SWITCH and charger harness...

Thanks a lot for your responses, I have the Super Brain 977 charger. It SAYS it charges LIPO's, but i have heard mixed reviews about this charger. Does anybody have any input on this charger, i don't want to use it if its going to ruin LIPO's.