i've had the opportunity to install several shockwatch systems on a couple of our customers. The install was fairly easy but it seems the customer has to have the network access setup before they can go online with the systems. So far to this day one of them i have of yet to hear that they have successfully done so. One other customer has incorportated these into thier system using a wireless access and after speaking to the operators and the manager they seem to like it. The system monitors the truck access and if there is an impact it immediatly flashed up on the managers screen and sends impact data such as speed, time of impact, the impact force etc.
The tricky part is tweaking the system so it wont pick up erroneous event triggers from just bumps in the floor. The process took about a month to work out the kinks but now they seem to love it.

As for Davis Derby? Never heard of em
maybe they will come around here eventually, if they are worth a look i'm sure my sales people will look into them.