Poco F3, 128 GB internal storage (non-expandable). More than enough for me. I don't film 4K videos, nor keep a lot of photos on my device. I could probably do with 64 GB with my uses and custom rom preference, but it was financially inefficient compared to the 128 GB variant.
Keep a cloud storage on the side or a NAS at home and anything above 64Gb will be a hard sale, depending on how much you film/record with your device.
My Redmi Note 4X has only got 32GB. It's not enough for my usage and like some other manufacturers, Xiaomi removed the ability to move apps to a microSD card to free up internal storage.