I haven't personally lowered my new Jetta but I have used both springs and coilovers on my previous cars. By far coilovers is the best option if you're doing daily driving. Lowering springs is also a good option if the funds aren't there but just have in mind that they will ware the rest of the components faster since they weren't spec'd with lowering springs. I would invest in coilovers or even bags if funds weren't an issue personally. I see that Solo Werks is the most affordable option out now going for just under $500 for the MK7 Jetta.