Magento – how to apply and show qty based discounts

I'm pretty new to using Magento, I am running 1.9 CE. I have messed about with configurable products, bundled, simple and grouped – but in all honesty I think I'm going about this the wrong way.

Let me set the scene…

The store sells single sheets of A4 paper in various different colours.
I have added the A4 sheets as simple products.

I'm looking for advice on how best to collate these products with various options and promotions, for example – I have then created a grouped product named A4 and added all the different colour simple products as associated products linked to the grouped product…. this then gives the end user the ability to set the quantity for the different colours. For example,

End user visits A4 Grouped Product and is presented with the different colours for each sheet. They can then select the QTY of each colour that they would like.

1x A4 Paper (any colour) cost £5.00
5x A4 Paper (any colour) cost £15.00

I have managed to create a Shopping Cart Rule which applies a discount when applied to the cart however, I need the ability to show the price prior to being added to the cart.

I cannot seam to apply catalog price rules using QTY.

Any assistance would be greatly appreciated!