Ok, so this heatsink aswell.
http://www.rc-monster.com/proddetail.php?prod=RCM01 Then go with the Feigo 8XL on 12 cells.
As for lipo, it is too expensive to start. I have the equipment but would like to try out NIMH and deal with that and then see if I am ready to step up.
What exactly does the UBEC do, and how do you set it up?