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I am about to become a first time mom and am planning on breastfeeding. I have to say this breastfeeding thing seems a little bit scary and confusing! I am leaning towards the harmony or single deluxe pump as I only need it for occasional pumping. I was hoping someone may be able to give me some advise on the best way to store the milk. Between the bottles, plastic containers, and storage bags, does anyone have any recommendations or advise? They all seem to serve the same purpose, but I'm sure one is more prefered than the others. Originally I was thinking of using the bags as they look like they would take up less room in the fridge but I'm not sure. From what I've seen in my research all of the above mentioned storage methods would fit on all medela pumps. Any advise/input would be greatly appreciated.

I am expecting now, but previously used bags to store my milk in fridge or freezer.  Noticed another post online where they used a cookie sheet in the freezer to flatten the bags for easier stacking..I thought that was a fabulous idea and plan to try it myself. 

The bags are the up-front most economical. The bottles are expensive. A cookie sheet in your freezer may be too big for flattening. I am using a sturdy paper plate in there to get a slim profile (flat) bag of expressed breast milk. In a regular freezer they are good for up to 3 months. In a deep freezer they are good for up to 6 months. The flattened bags are also better options for storage when space is limited (which is why the bottles might not be your best choice). Get inexpensive plastic trays to organize your milk within your freezer/deep freezer. Use oldest first (duh), which is why you want it organized. The bags also can be used on your shields while pumping, negating the need to clean/sterilize the bottles. You would just need to clean the shield, membrane, & the yellow thing the membrane attaches to.