Ouch...BOTH coil packs and plugs? I've bought cars for less than that must have cost....
Are you happy with the RL? Here's how mine did on M1. About to pull another sample this week as the A service is due and I plan M1 again...
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2982174/M1_0W40__8,946_mi_Mercedes_V-1#Post2982174