The best thing about the unit is the size and weight. It fits perfectly in a small pocket and is about the same size as my phone. It comes with various connection ports and seems to plug into just about everything I need. If you have a device it doesn't have a connection for, just use the usb cable supplied with your device. The Ripa 2 has a standard usb port for charging devices and a mini usb port for charging the unit. The Ripa2 has only 1 button and that controls the outgoing voltage as well as the charge display. It's not the most intuitive press cycle, so read the directions so you don't muck it up and send too much voltage to your phone. The unit can output 5v for a regular usb or 9v for an Ipad. Handy, but the unit must be in sunlight to output 9v.
Overall, it's a great unit for what it's intended to do. It's not high powered enough to keep you sustained in a long term emergency but will prolong your power needs for quite a while if you are careful with your power usage. If you are looking for something to keep your battery powered items charged up and running for an indeterminate time frame, you will have to look into the Brunton line of solar films and chargers. They are expensive but have a greater output for higher discharge items.
UPDATE 10/18/2014 Unit died. Went to a Jackery 12000 MAH unit and a coleman 12v folding solar panel.