Offending I wasn't, but I don't like postwhoring. Especially in my threads.
Salvatore, the battery type is listed in the features of the first post. If the question was "which brand ?" regarding your issue with batteries, those are DX ultrafire (blue). Mounted as a pack.
If you have some that can't be recharged, it can be the protection PCB that failed and stays open. You can still remove them and build your own custom battery pack using a 2 cell protection PCB from battery junction for instance. Or just buy replacement cells at DX. I'm getting myself off topic, sorry about that.
PC can be said to be "less complex" since it proposes less features. The basics are the same, power supply voltage, luxeon leads, 3 pads for the switches. Then no FoC, only 2 accents. Still, you can wire up a progressive power on indicator (mirroring the luxeon flicker) and a rumbling motor. So it's slightly simpler, but not much.