Lipo setup advice please

[Trick440]

I have a Revo with the Neu 1512 2.5d/f, Quark 125b controller.

I'm looking to run 4 cells. First question, a 4s2p, is that considered 4 cells or 8?

I'm thinking about getting the NeuEnergy 25c 5000mah 4s pack. Or possibly a True Rc pack.

I need a charger, I want something that is AC powered. The HYPERION EOS0610I looks good but I think its only DC? Some chargers, charge faster than others? Also I need different connectors for hooking up different batteries to the charger? (eg. if I bought 1 NeuEnergy & 1 True Rc)

Sorry for the scattered questions. I could use your recommendations and/or suggestions. I need whole lipo battery setup, from battery, to charger, to balancer. I want the best bang for the buck.

I need to stay 4s or under, if I go more I need a seprate battery for my servos with the Quark? I think thats what i was told.

thanks and I appreciate the suggestions. Its all confusing to me.