Just check the clearances around you before you lower it. I was considering lowering mine but a few encounters with some speed humps and car park entrances/exits have had her bottoming out so I think I may be leaving her standard!
I've got mine lowered on Eibachs, haven't encountered any issues as yet and does improve the arch gap (only 10mm lower back, 20mm front if I recall correctly).
mines around 10mm lower than stock..... no issues at all, i run a 3 way track biased coilover setup, i tried to set the car at stock height but these wouldn't allow, lowered cars look great but aren't too practical imo.
