If you want a comfortable ride with a little drop and you do not want to spend big $$ get springs. Recommend H&R but many different options out there. Closest to OEM ride quality.
While technically extra travel on a shock will put extra strain on the valve body, it will not "wear out faster" by any appreciable / noticeable amount. We're talking 2-5k mileage difference over the life of the car traveling an extra 1-1.5" you'll get from a decent spring drop.
Do NOT buy cheap coils. Around $800 for decent coils (ST IMHO are best bang for buck). Cheap coils are cheap because the valve bodies are junk and will ride like a truck.
These opinions/recommendations are made under the assumption that you're an adult and this is your daily driver and you value your ride quality, not what scene kids think.
Otherwise buy some racelands and go nuts
They see me trollin', they hatin'
I just put 18'' wheels on my car and decided I need to lower it maybe an inch. Definitely cannot afford coils after what I paid for wheels/tires. Therefore, I decided to go with springs. Anyone know what's the best bang for the buck? I hear H&R are good one's? I have a 2012 Jetta TDI.
DO NOT GET COILOVERS unless you are planning on corner-balancing them!
Your ride will never be the same if you do not corner-balance them.
Our car; all cars are designed to be balanced from front to back and from right to left. We can change those balances, but only in measured terms. Don't believe me...find your largest friend and zip around with him/her in the rear right, and rear left, then in the front pass and you will see exactly what I mean.
Springs are designed to mimic your car's weight distribution, or slightly better it.
A solid corner-balanced coil-over setup will sharpen your car's balance even more.
It's relatively inexpensive and worth every penny. Anybody that tells you it is not worth it has not ridden on a corner-balanced setup.
My$.02 for you? Get a set of progressive springs and be done with it. If I recall, you have a GLI. The suspension is already made to run lower from the factory. If you are planning on lowering it the range you speak of, the OEM shocks will suffice. You may lose 1/5 of their life, but you can always buy something new then; we're talking at least 50K miles or so away.
Eibach is the easy way to go, but you may find the drop not enough for your needs. Ask others what progressive springs they have used and liked or find a good vendor or two and ask them.
What is a progressive spring?
It is a spring that has a higher spring rate (firmer) but the final few coils on the top and bottom have a lower spring rate (softer). That will give you a near factory ride quality until you push it harder, then it will firm up.
I recommend coils.