I use a kei truck for farming. They are incredibly pragmatic little vehicles. They are very capable driving around on dirt/gravel agricultural roads with 4WD, and they are inexpensive and robust enough that you can really beat them up and use them as a tool without worry. Repairs and replacement parts are ubiquitous and inexpensive.

They aren't comfortable to drive at all (although just having A/C at all on a hot summer day is a godsend), and I wouldn't want to do longer trips in one - although you certainly could in a pinch.

It seems like Toyota/Scion is just testing the waters here, and I'm not sure how successful they'll be. But I hope there is a future for kei trucks in the US.