Brad,
I've worked on HTP for many years and feel pretty good about the quality. They aren't made in China or seem to be from Italy like so many others that I work on. (I don't think anybody knows besides HTP). The style and quality are similar to some Swedish or Danish units, but nothing mainstream (Kemppi, Migatronic, etc.).
Their customer service is good, and parts are cheaper than others who
import the same units.