I have to say that at $285 for a 10hp version, it is an attractive option pricewise..I'm not seeing any ventilation slots so Im guessing that it isnt an electronic type inverter,which would require a heatsink and cooling fan for the mosfet/IGBT power transistors..I'm thinking this is a capacitor static converter in a compact enclosure. The actual VFD drives from China aren't that much more money and are reliable as ever these days..I used to buy only Toshiba VFD drives and the eBay China-made ones are almost as good. You can program the VFDs to go 100% full-output depending on how you strap the control terminals and programming..The cap static converters don't allow the motors to develop full rated horsepower like a VFD drive or rotary converter will..so for a single motor one of these DPS things might be OK depending on HP % of load on the motor. They do look pretty compact for building into a tight spot like your ironworker. For my money I'd go VFD.