After 9 weeks of waiting, picked up my 550-6 Wednesday. First stop (at 3 miles on the odometer) was my friend's garage lift where I switched the shifter to a Rogue Engineering SSK/WSR setup and replaced the clutch delay valve with a Zeckhausen modified version. Taking my time, it took about 3.5 hours car on lift to car off lift.

In the two miles prior to the switch, I did note that the stock shift throws were a great deal shorter than the stock shift throws on my e39 540-6. BUT, the Rogue SSK on the 550-6 is snick-snick sweet.

Last pic is comparison of the Rogue SSK to OEM. Two items on left are shift lever - note additional length on RE part (right shifter) below the pivot ball which is principal factor in reducting throw. Two items on right are the shift rods that connect the shift lever to the transmission. RE part (right rod) is machined of stainless and weighs by my guess twice what the OEM rod weighs which provides smoothness thru inertia to the fore and aft motion of shifts.