Alright, so let's see here. MSRP for 1 booster pack is $4.00. You get 2 in each starter deck, for a total of 10. Based on that alone, depending on your shipping costs, this is a pretty sweet deal. Oh, and you also get 300 other cards. Most of them are bulk, but there are a couple sweet cards.
JimNThere's a lot more cost effective ways of buying booster packs. This is an alright deal if you really want the intro decks but I would caution people against jumping on the deal for the sake of the extras and a few useful cards