Another update,
I have come to a compromise, I didn't want to modify my lights/wiring permanently just in case I need to make a warranty claim on my xenons. I wanted some plug n play LED DRL's. I have come to realise that at the moment that isn't going to happen.
Here is what I have done, it's a slight modification in that there is a little bit of solder involved. The solder can be removed if need be. The resistance of these new LED DRL's is very close to what is required, I spotted this when I found that they only threw an error when they were warmed up (some will know that resistance changes with heat) Having already done this same mod to a previous set of LED DRL's and it failing I decided to have another go. I'll stop waffling on now and post some pics.
Solder a 5w5 bulb onto the OEM bulb holder on a 4 inch tail then fit the LED DRL.
Insert the 5w5 bulb first and make sure it tucks in a corner, then clip the bulb holder in. As you can see when the DRL is off it looks like OEM.
You can just make out the 5w5 bulb at night with the correct camera settings
During the day or dusk the LED DRL totally overpowers the little 5w5 bulb and it's not really visible.
I think you could pop the 5w5 bulb in the engine bay if you wanted to but this would be hard work and require slots cut out to allow the wiring.
I'm happy with this as it is.