Is my shipping setup causing issues with free shipping?

[WebfactoryUK]

Hey,

 

Basically my client doesnt really want to weigh everything they have and postage price doesnt depend on the price of an item so I was hoping I could set it up in a simpler way.

 

I just created them 4 shipping options.

 

Royal Mail Standard Small

Royal Mail Next Day Small

Royal Mail Standard Large

Royal Mail Next Day Large.

 

I then set the price ranges from 0 - higher than anything they sell for all options.

 

Seems to work ok as far as they can just select which options they want available when adding a product.

 

Problem occurs when I enable free shipping by typing £25 in the box.

 

Everything changes to free shipping even if its only £4.

 

Am I doing something wrong or bad?

 

Thanks!

 

Sam