Yes, a good pump is very important to empty the milk in boobs. Hospital graded pump is better at clearing boobs effectively. I used Ameda pump and it is not strong enough to pump out the milk so I used back my medela manual pump where I can better stimulate the let down and strength but the downside is only can pump one side each time.
You might want to try Spectra S1/S2 which are hospital graded pump.
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