PI springs are always good and cheap, mine has been running a 35mmn drop on PIs for years and its the best mod I ever did. Best to change the shocks at the same time for some designed to work with a shorter spring. Koni adjustables are what I use, theyve never let me down.
You can run the original shocks still but they will wear out a lot quicker and youll eventually have to change them anyway.
You will find suspension components will wear quicker with a lowered Clio because the driveshafts are at a weird angle and it just puts more strain on everything. 35mm isnt a big drop, things like bushes will go first, but its not a hige problem. Certainly the handling benefits outweigh the disadvantages by a long stretch.