Im looking for suggestions on a good DC inverter for my Jeep. I would like to power up my laptop as well as a cell phone and a few other small devices and would like to get a good inverter with a nice, clean signal, and not a crappy radio shack unit. I know some are better than others for this, but just not sure which ones to steer away from. I was looking around the 200-350W range, any suggestions?