I bought this pump as I wanted a double electric pump and this was the most reasonably priced by far. The pump is easy to assemble, use and keep clean. I have been using the pump to exclusively express my milk as I found breast feeding too difficult with such a hungry baby.
Double pumping obviously halves the time needed to express but this pump also lets you pump one breast at a time if preferred.
Another feature that I like is you can control the suction. You can adjust the power according to your preference. Spare parts are also easily obtainable should they be required.
It's lightweight, can be plugged into an electrical outlet and can also run on batteries. This makes it very portable.
There are two minor negative points. Firstly the suction has only one speed and is not designed to stimulate let-down. The other is that the pump is slightly noisy, however as expressing tends to be done in private I have not found this to be too much of a problem.
In conclusion, I am very satisfied with this product. It does a very efficient job of collecting precious breastmilk.