Where and what size should I get the Someday fragrance by Justin Bieber?

I'm looking at all the stores that have this perfume, Someday by Justin Bieber. At Nordstrom, it is $35.00 for the 1oz bottle and $45.00 for the 1.7oz bottle. At Sephora/Jcpenny, it's that same as Nordstrom's prices and sizes, plus same with Carson's. You see, at Macy's, its the same too, but then there is a 3.4oz and its $10.00 more that the $45 dollar one which is only 1.7oz...I want to know which is really worth my money for buying this Fragrance that girls are really obsessed with right now. Macy's has a size that no other store that I've seen has. So if you don't mind giving me your opinion, Where should I get the Someday perfume, and what size should I get? Thanks. :)