For '06 and newer you HAVE to remove the front bumper cover due to a structural steel upright to the rear of the light assembly that is not there on the 745's. I tried going thru the engine compartment only - no joy! I had a smaller independent european auto shop do it and it took them 1hour. (Local BMW dealer quoted me 2.5hrs labor.)
As far as the actual LED's - I bought off Ebay from euroefx (efx) for $50, and they are high quality and great in appearance.