So Joe the setup I have is:

1x: http://www.hobbycity.com/hobbycity/s...idProduct=6879 (This I use at home, at our flying field we installed a 75Amps 12VDC power supply)
With this I can charge at 5Amps (which is about 15Amps on the primary side)

2x: http://www.hobbycity.com/hobbycity/s...alance/Charger

6x: http://www.hobbycity.com/hobbycity/s...idProduct=7654
Now they are rated 2C for charging; when I bought them they were 1C. That is why I have 6 packs (=3 sets). I guess you could have two packs when you charge at 1.5C.

If you charge at higher then 1C you would need a heavier power supply: http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9205&Product_Name=25A_14 v_DC_Power_Supply_for_Chargers_(350W)

However, since the packs cost 65$ each, I would still go for 6 packs.

In this way I can fly as much as I want, there is always a charged pack ready when using two chargers.

When I started I bought two packs with one charger and one power supply and bought four more packs once I had my plane almost ready to fly, just to spread the cost.

Each pack has flown over 50 flights with no degradation sofar.

Volkert