What surprises me (or i missed it completely) is the use of a waterproof ESC. I use (cheap ass) Hobbywing ESC's on al of my rigs. The G6 even had to spend some time in the salty water of the sea so i could take some pictures and small waves submerged the car every now and then.
The receiverbox i fillec with a layer of plastidip. Dipped the receiver in plastidip. Put the receiver is in a balloon. Did put it in the receiverbox. Poored on more plastidip. Covered it totally. Did put a piece of old foam (after plastidipping it) in the small gap where the wires enter the box. Been driving like this for almost 2 years now. I submerge my cars on a regular basis (because i like doing that) and never had an issue.
As for the battery....
I also believed the stories about lipo's and water. But decided to put it to the test on video. I drove my car into a creek and did let it stay there for half an hour (there was a big clock in the frame for the viewers to check that i did not cheat). After half an hour i drove it out of the creek like nothing had happened....
What motor are you using, stock?
On the subject of water, how do you care for the bearings?