@Beefyheart: Now, I'm not 100% sure, but I can post what I know firsthand.
TRU just had a sale recently where they were selling the starter packs at $39.99 which is the lowest price for starter packs that I've seen so far. (I personally price matched TRU at Best Buy and picked up the console version with the exclusive Volcanic Vault figure, nothing special about it though really)
TRU also overprices their individual figures by at least $1 depending on the store and their packs are overpriced by at least $5 over other retail outlets from what I've seen.
All that said, if you take advantage of the current sale and pick up a starter pack and get two adventure packs plus pay for shipping and taxes, you'll be paying approximately $84 for everything.
In contrast, I picked up a starter pack at $40 and found two adventure packs at $20 each, so I actually ended up paying around $88 after taxes...which is $4 more. ...not to mention all the gasoline I spent driving around...
TL;DR - So yea, pretty good deal for the set right now...definitely the best I've seen so far.
The base game/figures are pretty fun too and you can beat the game (I unlocked all the achievements on the 360 version) without needing to buy anything extra.
Hope that helps you out.