I remember we used to use those for our engineers years ago. The main reason was due to them being about the only such device you could use outdoors which was quite important for such a device.
Back around 2006, we'd been using them for some time and I was organising getting in a refresh when one of the other IT guys who was managing a different fieldforce project stormed in and accused me of "adding another piece of kit to the portfolio of mobile kit!" Apparently he wanted to know why I was buying in these tablets when he had decided his guys were all getting Panasonic Toughbooks.
I simply said "Its not new tech as we've been using them for the past four years! Oh and I guess you tested the Toughbooks screen for outdoor use as well?...Cos these tablets are about the only device that works outdoors!"
He went quite pale and ran out of the office. I don't ever remember seeing any Toughbooks after that.