Why spend so much for a true sine wave inverter? Some devices will ONLY operate on true sine wave--laser printers, for example, and some medical equipment. If you need an oxygen concentrator in your rig, it might not operate on modified sine wave power. Some cordless equipment battery chargers won't work with modified sine wave either. If there's any doubt, you'll need to contact the manufacturer of the device you'll be connecting to inverter. This doesn't mean you'll be forced to run out and by a costly sine wave inverter to run everything--you could install the lower cost inverter to operate most of your rig; then purchase the more expensive inverter and size it only as large as required to operate equipment that won't operate on the modified sine wave power.