I have a new LF1100 + new charger for sale in the Trading section.(Bought from japan.)
The LF1100 gave me good speed and time.
later I remodeled my SS to fit my Nimh packs, (3000mah) these works well with the sport tuned motor and 105 esc...BUT I get overheating.
Will try this weekend to go with the lower gear ratio and see if that helps.
the two batteries you linked will work well (If you dont get overheating like me?), the overlander will fit easily, the wheelspin will need some modification of the placement of parts inside the box.