I would suggest getting the best quality kit you can find (TRS) a relay harness to power it (TRS) and see how you like the results of HID lamps in halogen projectors. I have been very happy with mine and I NEVER get high beamed by oncoming drivers. There are many, many people who will tell you that the only way to HID is a full retrofit, but I respectfully disagree. The headlights on the 5 seem to take to HID quite well. I do sometimes wish for a bit better beam spread and a sharper cut-off, but I'm not willing to go to the trouble of a full retrofit for those (relatively) small complaints. If you do decide to go full retro, I can't recommend TRS highly enough, they are the best in the business and they have the best customer service out there, up to and including walking you through your first retro over the phone. No I don't have a sponsorship LOL.... Be aware, if your 5 has DRLs they will have to be euthanized to allow the ballasts to survive, a small sacrifice for infinitely better lighting IMHO