Everyone at my track runs lipo. The servos are faster and will have more power because of the extra voltage. Pay attention to your voltage though because if you run the battery too low, you can ruin it. 3.7 volts per cell is about as low as you want to go. Of course, make sure your servos and reciever are rated for lipo. Sometimes the documentation with recievers is a little confusing because they will say "nominal voltage 7.4 volts". If it says that your ok to run lipo, even though a full lipo is 8.4 volts.

I don't know much about LIFE other than they have less voltage.