Faygo or their store brand will be all the much cheaper.
I can find soda for $0.30 a can lots of places. When specials are running it's possible to purchase four 12 packs for $11, three 12 packs for $10, a 24 pack for $6, etc. All of these end up being less that $0.30 a can... some even with sales tax included.
That's $3.50 / 12pack - which is probably the average around here (non-sale price of $4, sale of $3, or best at $2.50). This is pepsi line at a Krogers, so name-brand product & store.
Wow, that's cheap. Name brand soda (specifically I'm talking about Coke) is $6/12 pack normal price here. I'm not sure who buys it at that price though because it goes on sale all the time. The most common sale I see is 3 for $9.