hi,a few of us here in ireland are using lipos in our b4's with no problem.we actually get through a whole day just using one pack(just stick it back on charge when you come back in.theres no drop of in performance)depending on what cells you get e.g trakpower 3200 or 4900,you may have to adjust the height of your battery strap(just unscrew the retaining screws abit)and maybe add some weight to help with the setup as lipos are lighter.
you can run them on a speedo that doesnt have lipo cut out just be carefull not to run them down to much(generally wouldnt go past 5 min race plus some warm up laps myselfprimarilly because it takes to long to top them up ,although i have seen 10-11 min runs without a problem)as dropping a lipo below its min voltage is what damages them and this is what the cut off prevents
jeez think thats the most iv ever typed hope it helped
