Firstly you haven’t mentioned how old your little one is. What is the reason you have been expressing in the first place?
The answer to your question lies in your preference. If you prefer to breast feed your baby directly at some point then I would advice to avoid bottle with nipple. It’s a lot easier to extract milk from that than it is to extract from the breast and the baby tends to become lazy and frustrated when breast fed. Palladay or spoon is advisable to avoid nipple confusion.