If you drop it that much (3"), plan on getting new struts/shocks all the way around, along with a new alignment and a camber kit. Add all of that to the cost of the coilovers/springs and you are looking at a small chunk of change...
Max drop without replacing struts would be around 1-1.5".. Even then they are gonna wear out pretty fast..
Plus, you won't be able to drive it all that much due to the chance of the tire rubbing the well is too great. not worth it IMO, regardless of the brand.
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