Whistler has been manufacturing their DC to AC power inverters for years now, which means you can count on their quality and reliability. All of their models come with a two year warranty, robust features and high surge for startup. Thanks to their “Smart Surge Control”, the Whistler inverters attempt to start loads above the continuous rating for up to 10 seconds. That can come in handy when try to start those pesky old motors or compressors. Whistler recently redesigned their power inverters giving them a new look and feel, but what remains is their reliability day in and day out. As far as a modified sine wave inverter goes, the Whistler line of inverters has stood up over the test of time. The XP line replaces the PRO line that was a very good seller, and ranges in sizes from 100 watts to 3000 watts and only come in 12 Volts.