IIRC, somebody bought a similar unit off ebay and had a switch go bad quickly. At least HF will exchange a bad tool during the warranty period, dunno about the Ebay ones. OTOH, a spotwelder is just a transformer, a switch, and some tongs. Unless you severely overload it or physically snap something off, they should all be about the same. The HF one looks identical to the $600 Miller unit in the catalogs with the exception of the tongs. A switch can be rigged up if necessary.