I think a lot of us would like to be using some sort of dc to dc power option. Nearly all the devices I use on my boat actually run on dc power (laptop, cellphone, camera, vhf), but have ac adapters to charge.
I don't have any experience with the products you are mentioning, and probably others don't either. That's why you aren't getting much response. If you use the iGo, I would love to hear about your experience. I think I have seen the adapters in radio shack. Personally, I use a cheapy 300 watt inverter from radio shack. It gets the job done, even if a little inefficiently.
Gemini Catamaran Split Decision