Quote: Originally Posted by all_bran
Both sets are safe when used on their own... but what would happen if I did both as a plug/play installation?
HELP!
There's where you wrong already. Neither one by themselves is what I would call "safe". Obviously by the several posts here, the MFS is our biggest weak link. That and the wiring alone was never intended to operate under the current draw of HID start-up or high wattage halogens. That right there should be enough concern for you that you should of upgraded a harness while you were upgrading your headlights or fog lights. I'm sure the Modern fog light kit comes with a upgraded harness so you would be ok there, however I STRONGLY suggest you also upgrade your headlight wiring with a upgraded relay harness. I have posted the diagram here in several threads. Its VERY easy to make and costs next to nothing!
There is your expert advice.