Well, I don't really need to prove anything. But I do want to make a contribution by making an example of what is feasible. On the other hand, there is a part of me that want to test my physical and mental boundaries, as well as my planning and preparation skills - all within the very restricted confinements of traveling on a Vespa. I also must say that I do have a special fascination towards Vespas and all sorts of other crappy vehicles. In some instances I might even prefer to push my own Vespa than to be riding a twist and go scooter. My scooters and I have been through hell and back... it's like being married I guess - you just don't trade up. There is much adventure to be had in the struggles.
As for time, I don't have much spare time at the present. And, for me there are two types of trips. One like this one which is more about the sporting aspect and getting a quick glimpse of the world from the saddle than it is about interacting with the world I pass through. There will not be that much time to interact and reflect on this trip, but there will be other trips somewhere down the line where this will be prioritized. But my experience is that coming along on a Vespa causes a lot of commotion and interest - which will at least give me a tiny sample of the people. As for the rest of the rally competitors, we won't see much of them as we will be waaaaaay in the back.
As for reliability, I will equip myself in such a way that I should be able to handle just about anything that comes my way. And from experience, I will need to... I will have many breakdowns and punctures. I will also be traveling with two pals... I will be as safe as I can be. Luckily for me, I enjoy the challenge in having to turn a wrench and fixing things (even though i suck at it).
Some day though, I hope to be able to take a long sloooow trip on something more "suitable" than a beaten old Vespa (like a new Vespa.... or a bimmer or Ural). But, as my current life is tied down with too many responsibilities which I am reluctant to give the finger to (a one year old daughter, a three year old son, a wife, a dog, employees, a career, a serious mortgage, a garage full of scooters that need some TLC, and a home brewery that needs to put out some more

), I can't do long trips at the moment. My only other opportunity is to do short satelite trips every now and then - save up some money, fly in, ride around, fly out... and quick enough not too not have caused too much havoc at home. I hope that others in my situation see that there is an option to dropping everything and be gone for a very long period - with all the implications that may have in the life after the great trip. I argue that you can have your cake and eat it too.
Somewhere down the line, my kids will be old enough to come along, my career and my wife's will survive a year off, and I can handle my debt without having to sell possessions that are dear to me or that would imply a great financial loss if I had to buy them back upon my return.
There was a couple from New Zealand that had two children aged 6 and 8 that went on an RTW on two inexpensive motorcycles - with no prior experience, and loved it. In other words, I am hoping that in 5-10 years, this dream will come true. In the mean time though, I am not willing to sit on the fence and wait for something that might be, not when I can get a small taste already now. I opt to spend the little time I have, the savings I have at hand, using the ride in my garage, and go go go.
There is another great benefit of doing the world bit by bit in small pieces at a time, there is little risk of becoming homesick or suffering from cultural fatigue and boredom