Really no improvement in thrust, just duration. I'm getting about 7-8 minute flights with the 3300 nimh packs. That's if I'm heavy on the throttle. You pretty much have to be because of the weight. It still won't take off from grass on the 3300 nimh packs, but you can hand launch it. I have 3 of these packs, so that helps. The lipos are the way to go with this plane though. More power and performance and longer flights.