Basic coil springs from H&R cannot be adjusted like their coilovers can. H&R lowering springs have a set height in which they lower the vehicle and each product has this specified. H&R offers them from a very mild drop to an extreme drop of more than two inches. Their coilovers are very different because they can go from stock ride height to more than three inches of drop for any specific vehicle.
If you are debating which product from H&R to go with, then you need to consider the types of driving you do and if you want adjustability. Their non-adjustable products only give the specific drop and can be used with your stock shocks. Since H&R coilovers can be adjusted, they are recommended to be used with aftermarket shocks since your OE ones will not be able to handle them. Also, coilovers will need H&R camber bolts to correct the negative camber when lowering the car. On the other hand, the non-adjustable ones from H&R may not require the use of aftermarket shocks or camber bolts.
H&R lowering springs are a one-time deal and do not need to be adjusted by any means. Once they are installed, they will take a few weeks to settle and that will be the ride height for the entire life of them. Adjustable coilovers can be raised and lowered as many times as you want, but it does take some time tuning to get them right. H&R makes more than 3 different styles for each so you are sure to find what you need. Both products from H&R will give your vehicle an enhanced appearance and more control on every type of road surface.