QuickJack 'legs' for garden building?

[headey]

My plan is to build a wooden frame base, floored with external ply. Rather than build a cement slab to rest on, I wondered about using piers to raise the wooden frame off the ground. I could cast them myself, or I've seen pre-cast concrete slabs, formed to hold timber. However, a simple spike or auger driven into the ground that can support the base seems like the simplest (and possibly cheapest) option. Does anyone have an opinion about QuickJacks (or anything similar)?

http://www.a1sheds.com/quickjack-pro-ad ... 1398-p.asp

[steviejoiner74]

I'd probably just use 6" concrete blocks laid on the flat to build up as piers. Each pier wouldn't need much of a concrete foundation and it'll be relatively cheap and strong.