Our neighbour gave us her used Medela pump in style pump that she used for her 2 kids. Would you use it or get a new one? I’m concerned about it being an open system and not knowing our neighbour that well, and also pump strength if she used it already for 2 kids. If I buy the replacement parts, it’s over $100 - so should I just spend the extra $250+ to get a new one? Or use the borrowed one?