i have a chance at a set of koni 40mm lowering springs has anyone used these??? r they worth the money???

i had koni springs on my 2.0 fabia and they do firm up the ride nicely, they were very good value for money too, at the time eibach springs were 'king' but they were quite a lot more expensive... i did often feel that the koni rear springs were too hard for my liking but i guess thats a product of being a family hatchback desgined for people and a boot full of stuff i guess.