Glad you like it. The main thing is that it is working for you. The emptying once a week bit comes from the builder, not me. If you are getting more out of yours, that is great. The longer you can wait before emptying, the less like poop the contents will be. My Nature's Head holds 6 weeks worth of material, with two people almost full time (not large people, mind you, and we will use a toilet ashore if the opportunity presents itself, so our success rate might be skewed a bit high). But 6 weeks! That is soooo good. The head on my boat went from being the biggest pain in the butt, after the engine, to being an almost unnoticed thing. And, I now have 30 gallons of fresh water where that holding tank used to be. (in a new tank, of course!)
Regarding leaks from the bottle...hmmm that is strange. I would think they overfilled it. The extra bottles, if you chose to buy one (I did not, no need) are $40, I think. It's nothing like a milk jug, it's quite heavy duty, and I like that. To make it leak, I think I'd need a drill or a saw. It's heavy, molded plastic (there are no seams) so there is really no way for it to leak.
If I remember correctly, Sandy (the builder) says the unit is good for 10 or 15 uses per person
if a couple is using it. Which sounds about right: a couple using one for two weeks equals a single person using it for a month. Although I could use it longer than that, if I needed to. I empty it whenever I start feeling some resistance to the paddle as I crank, but that's just a convenient signal... I'm guessing I could fill it twice as full. As easy as it is to empty, though, there's no real point in doing so.
No, the complaints about leaky urine containers were definitely because they were leaking, not because they were overfilled. I was surprised myself, when I read them. Do they have some sort of valves or slip fittings that can go bad?
Milk jugs and water jugs are also molded in one piece, you know... I've never had one leak on me in the fridge, unless it had been severely mangled before it got there. So I don't expect them to leak in the C-head either, especially since I replace them whenever I have an extra jug handy. I do so because I'm too lazy to rinse them out, not because I'm afraid they're going to fall apart on me.
I'll admit that because I'm using one-gallon jugs, I usually empty them every other day. And if two of us were using the C-Head, I'd probably empty them daily as part of my morning ritual. But all I have to do is (again), just lift the lid and grab them. Then I can either cap them for later disposal and throw a spare in, or empty them and stick them back in the toilet.
When I take to the water with my new boat, I plan to stash drinking water in a row of the same type of one gallon jugs (I won't be making any ocean passages; it's going to be a lake boat). So I don't anticipate any future shortage of urine jugs...
As far as actual composting goes, I've been doing that in my secondary collection bucket, which has a vented lid. I just dump the new batch into it, and sprinkle a little water in to get things going.
edit: oops, my bad. The owner's manual does say 10-15 uses. But I definitely get a lot more than that out of mine, with no problems.