Hi
I bought set of 4 Monroe shocks absorbers for my 1.6 cabrio.
I'm interested lowering the car a bit,

I found a cheap Eibach prokit 30mm springs.
I also found AP coilbars suspension kit at almost the same price.

What would be a better selection?
Eibach + Monroe or the AP set that includes shocks?

I have eibach on my car and was the first mode I did more then 100k miles ago and am not regretting it. Also used new standard shocks to go with them. The ride is harder but easy to leave with it. The handling was transformed dramatically, from non drivable to exceptional predictable car, especially in the dry. In the wet you will need to invest in some good front tyres as the car understeers a lot otherwise. So as you already have new shocks you should go and try the eibach first. You can always try the coilovers later if you don't like the setup.

Lowered springs should really be matched to shortened shocks. Standard shocks will not perform correctly with lowered springs, OK maybe for an older car just driving but not for performance and long life.

I think if you just fit the new shocks and check everything else in the suspension for wear or damage you will be pleased with the improvement in ride, noise, comfort and handling of the car.

I don't really see the point in lowering a MK1 Punto cabrio... at that age it deserves some consideration and respect, not modifying!

Standard height shocks will be fine with 30mm springs, anything under a 40mm drop is generally considered fine for standard height shocks. Although you may find ultimately that a matched set of shocks and springs bought as a kit might result in a better deal than buying seperately - this generally results in a harsher ride however over some new good standard replacement shocks and slightly lowered springs.

As to which route to go down, I'd stick with good shocks and springs on a road car unless there are plans to do track days as well. Only reason i can see to legitimately choose coilovers over shocks and springs on a road car is if you are into really low 'stanced' cars.

So my answer is, it really depends what the ultimate aim and the use of the car is as to what is the best choice.