Yeah that's what I thought. It's only a hex pattern on the non-M. The OE that I pulled off wasn't keyed like the one you have pictured, and neither was the Powerflex bushing. It does look like the diameter of the M's LCA is larger from the picture. I wonder why they relieved material from all of the apex edges on the M bushing.
/// Auto => 6-Spd Manual Conversion | Apex EC-7 | Koni/Ground Control Coilovers | Vorshlag Camber Plates | Meyle HD LCA | PowerFlex bushings | GruppeM CAI | Shark Injector | 6000k HID's and Fogs | BMW European MTechII | BMW Performance Shifter | ACS Mirrors and Rear Spoiler ///
Last edited by TitaniumCranium; 02-07-2013 at 12:39 AM.
Reason: addional thoughts...