Just for info really in case anyone else is in the same boat. Was getting a good supply with my manual Phillips pump, but am expressing all feeds so it was really taking time.
So I bought a medela freestyle, thinking electric double pumping was the way to go, but it was taking forever and I was getting far less. The medela things were the right size so it wasn't that.
SO, I used the Phillips massage cushion in the medela breast bits and it's working a treat. Takes, quite literally, a quarter of the time from each breast for the same amount. Worth trying if you're struggling with your medela. Phillips sell spares!