Thanks for the input guys. I'm a bit too lazy to carry a battery to the pond every night. I'd rather gas it up every few weeks and just walk down to the pond. I'm leaning toward the Mercury 3.5hp 4-stroke. That should be plenty of motor for my 16 acre pond, even when my boys get older and weigh more. I like the idea of buying the ones on ebay pointed out by Cecil. They are about 100$ cheaper and if the shipping is free, that saves me 80$ that it costs at most other places.
