I have to agree with him on the HF "Duel MIG", I have a buddy who has had one for several years and the darn thing works just fine! He bought the MIG and the $199 TIG machines several years ago and we discussed them here then, for the money they seemed to be ok at the time and they are still going. I am NOT saying that either one is even in the same class as a Lincoln or Miller but they can work ok if the user is willing to accept the limitations and do so at a fraction of the cost. If someone is buying one of these things to use everyday or they expect to do more than just body work or maybe lawnmower repair then they will probably be sorely disappointed but for light duty welding on an occasional basis they seem to work ok, at least the two I know of are. That guy has done quite a bit of auto body sheetmetal and built a motorcycle frame with the TIG, he is also a hobby gunsmith and uses the TIG machine for that. The "Duel MIG" was bought to replace a cab corner in his Chevy pickup but it has continued to serve long after that little project was done, less than $400.00 for both a TIG and a MIG and both have done just fine.
These things are NOT heavy duty by any stretch and if someone buys either of them they can only expect very light duty from them but for some people that may be all that is needed.