MLRS discount prices

MLRS Books is offering a discount on their books until the end of the month. From their announcement:
We are cutting all prices by 25% on the first three books you order, and any above that number will be discounted at 30% - so books 1-3 are at 25% discount, books 4 and upwards get 30% off. This applies to each single order, and is not cumulative. Postage charges will be as normal - cost plus packaging.