Well, the original homemade composting toilet worked just fine. The only wrinkle was adding the urine diverting after the fact, which was a pain and not very elegant....a square blue NAPA funnel leading to radiator hose then with all sorts of adapters and such to eventually lead to 1-1/2" pvc. All the details on that toilet are here:
http://seanf.smugmug.com/gallery/1382138_5ZpVT
http://seanf.smugmug.com/gallery/1453494_gn4FV
http://seanf.smugmug.com/gallery/1991242_mHEKf
As stated, it worked fine. For use by one person, a bucket had to be emptied every 3 weeks or so. The cover material (wood shavings, etc.) were easy to find, but a little bulky to have a bunch on hand. Another small problem was that occasionally flies would make an appearance. I suppose this could be remedied through a more airtight construction.
The new toilet I just installed is a Nature's Head, which is the same concept, just smaller & more refined. It functions flawlessly. My only complaint (and it is a minor hassle) is having to empty the urine tank every few days. Here's what it looks like:
It's not cheap but it is a USA-made, well-constructed unit that serves my purposes.
If you decide to build your own, my two pieces of advice are:
1. Divert the urine, don't let it mix with the #2
2. Pay extra attention to airtight, fly-free construction. You don't want flies coming from the potty and landing all over your kitchen counters, food, etc. That could be bad.
Hope this helps
Sean