Springs will usually be a smoother ride, but if you plan to get shocks and things like that then it wouldn't matter if you got either. Also my friend has coilovers on his car, and some sand or rust, something made the coilovers so that they wouldn't adjust. He was telling me that he needed to clean his coilvers ever so often to keep them from getting broken or whatever. Also coilovers are ideal for show if you want to lower your car and make it look great, and if you live in an area where you get snow often, they can be great to higher your car so that you won't have to worry about being a snowplow during the winter months. Springs may not be adjustable, but they work great for anyone, as long as you don't get anything cheap, stay with good companies, it's much more worth it. Also if you plan to lower it more then 2 inches get a camber kit. Lastly, whats your ideal setup anyways? What kind of "coilovers" or springs you planning to get?