I have just bought a pair of Tech 8s - haven´t arrived yet and because of my large plates of meat I´ll have to wait a couple of weeks.
From what I saw, tried and what the shop guy told me the difference is essentially the inner bootee. Now apart from the word Bootee being a big put off, I have to say they are bloody comfy. I don´t know if this is really the only difference, but they were significantly more comfortable for my oddly shaped body. As for price - well I am relatively inexperienced off road and the chances of me ending up both off road and off bike are relatively high so I followed the kind of logic that Timolgra uses and bought something decent. Still need to sort out the lid though. In Spain it is only really easy to find Bell, Axo and AGV MX lids. Anyone have any suggestions? I normally buy Arai as they fit my bonce pretty well.
MX boots look the dogs, but as Simon says walking in them is really quite hilarious. So would not recomend them for "touring" if by that you mean, ride stop and look around, ride some more.