I finally went and looked at the $200 unit after the various discussions on this group. It really looks pretty good for what it is. The torch looks just like my name brand units, nice fingertip gas control. I really like the fully adjustable current knob, and it looks like adding a foot controlled 10K pot will be do-able. I found some companies that sell then for well under $100, although I haven't researched such things as sewing machine pedals, guitar pedals, etc, to see how many ohms they have or if they have a pot that can be swapped out. You can find these on eBay for a couple of bucks.
Right now I have an AC welder with a Sears high frequency TIG adapter on it. It works well, but is AC only and I want to get into thin steel sheet metal with a DC welder. Would it be possible to add the hi-freq to the Harbor Freight TIG? It would have to run off a remote switch, I guess, to operate only at the start. I asked the people at Hobart if my converter was ok to use on the Stickmate AC/DC welder I was considering, and they said it would work. But the Stickmate would not be possible to convert to foot control.
Maybe it isn't worth the effort if the HF does indeed use a lift arc start? I also have a water cooled torch on my existing home-made TIG, but I was using it for aluminum and I doubt that the HF would benefit from water cooling for the low amp applications I have for it.
Dennis