speedy - listen to Duster_360, teach you he can...
It is VERY easy to make 5S2P packs from the DeWalt battery packs.
There is an excellent tutorial by LBMiller5 on the topic here:
http://www.rcgroups.com/forums/showthread.php?t=599316 . Read in conjunction with
http://www.rcgroups.com/forums/showthread.php?t=587606. Not much soldering, although a little more if you do the solder-braid-in-parallel-across-the-existing-joints trick.
A 5S pack weighs within 2% of a 7-cell Sanyo 2400 NiMH set.
Be careful of these batts- they put up with lots of abuse but they can weld
themselves if you touch the terminals wrongly during assembly. I love them!
Regards
David / ICUBoy