Batteries/charger

I’m building an electric bicycle with a 36V 1000w permanent magnet motor. The bike is a Giant Stiletto like this one.

I’ve got the motor, controller and throttle but no batteries yet. I found some 14000mAH F cells batteries with tabs for $385.49 delivered that I am going to make into 3 x 12V packs (so that if in the future I want more speed I can add another easily).
Edit:They’ve also got 60 D cells (10000mAH) for ~420 del. so I 'll probably go that way and double my available current at 36V. I'll also get more Ah/.

Same company has this 36-48V smart charger for 52.50 delivered.

http://cgi.ebay.com/48V-Smart-Universal-Charger-for-40-cell-Battery-Pack_W0QQitemZ330171693236QQihZ014QQcategoryZ19167QQtcZphotoQQcmdZViewItemQQ_trksidZp1742.m153.l1262

So basically, before I pull the trigger on the batteries I’m asking you guys here if I’m pi$$ing it away or if this looks like a reasonable battery/charger solution. I’m open to other suggestions.