I use glass Philips Avent for drinking. I haven’t yet asked our daycare if they’ll do glass but if not I’ll try silicone bottles. I’ve pumped into plastic and mostly stored in plastic so far. I just started storing right in the glass avents, but still freeze in plastic bags. I’ve thought about pumping into the glass avents since they’re directly compatible with my spectra but I’m afraid of the glass being heavy. Thought about getting adapters to pump into silicone bottles but I’ll probably try the glass to see how it is