The twin sensor can sounds like a good idea IF just sitting there in the heat isn't just as hard on them as working in the heat. A friend put two in his and runs them both at the same time (no wasted spark).
The beans can's biggest problem is the mechanical advance? I have worked and been around tons of bean can airheads since they first came out and I almost never see any mechanical advance problems. The problem I see them having is a failed sensor but that is the same sensor in what everybody else is selling so I hear about tons of mechanical advance issues since they have electronic advance. The trouble is I don't see much trouble at all with the mechanical advance. IMO, the easiest probelm to fix is one you made up to start with. How is a electronic advance going to improve starting over a mechanical one? If your bike is set up right, how would you get easier starting? Mine starts the second I hit the starter with a mechanical advance. Sorry but I just don't get it.
If I was running around the world, I would get a can that has a easily replaceable sensor and carry a spare. The biggest trouble will be remembering where you put it 20 years later when you need it.