What do I need to go with the Medela Pump and Style?

I just ordered it with a prescription. I am almost 32 weeks right now and I would like to know what I need to go with it. It comes with a couple storage bottles. I was thinking of buying some more, and also some extra membranes!
What storage bags do you guys recommend? Are all the standard ones compatible with the pump? Also, how do you guys like the Medela bottles? I also noticed that the containers that come with the pump are sort of like bottles with no nipples, why? Sorry! First time mom here!
Anything else I should purchase?
Thanks :)