I'm using the Medela electric pump (single pump), costs ~$695, discounted 30% off, I think, from Wing On last year.... They have it at 荷花 too. AC/DC or battery operated, very convenient and not too expensive! But quite noisy.
This is the first time I have a baby and thus a pump. So, no other reference.
I am going to buy a pump too. I borrowed a pump named AMEDA when I was in St Paul's hospital, it was very good, very efficient but quiet. The Medela one I saw from Mannings cost $649.5 on sale, this one I think it's quite noisy, so I will buy AMEDA one, cost over $1000, in the next two days I will go to buy then will know exactly how much.