Got myself a 10x14 shed kit with floor this past week, opened it up yesterday and was horrified to see how they wanted me to make the floor. (I did anyways just to see)

1. they used 2x4's instead of 2x6's
2. They split up a 14' floor into 3 sections: 10x8 10x4 10x2 (what idiots....)
3. To get everything pretty on a pallet, they split up the 10' into 8' and then adding a 2'
piece. (Horrible design that addes seams to support boards)

4. They must have found the enchanted forrest of crappy wood

Anyway, the floor flexes at the seams, and is not even square...Do yourself a favor and build your own!

The company is "Handy Home Products" out of MI and Lows and Home Depot both carry their crap.

I AGREE!!!
I had a very similar situation. I bought a 10' x 8' shed by the Arrow Co. Lowe's had a sale where you get the Arrow floor foundation kit for free if you buy the shed.
Long story short-- The metal pieces from the floor kit are on the floor of my basement, elevating boxes of stored items in case the floor gets wet.
I built my shed floor with the deck blocks, pressure treated 2x6's and 4x4's.
This is the best way to build a shed floor, in my opinion, for the common home owner.