I finally took delivery of my '06 550 yesterday! There is SO much to like about this car - it was worth the wait to get it configured exactly as I wanted. One option I ordered is Comfort Access (CA). The basics have been covered in other posts here but I wanted to offer my observations after using it only two days. In summary: I think its a brilliant option that is well engineered. Here are my thoughts:

(1) Unlocking - with the key on your person (in a pocket or purse), if you touch the driver door handle, only that door unlocks. Just what you expect, same as a single push of the unlock button on the key fob. If you want to unlock the other doors (same as a second push), simply touch the door handle on the rear drivers's side door. Perfect - I have all the unlock functions of the key fob while leaving my key untouched.

(2) Starting and Operating - starting is the ultimate in simplicity: with foot on the brake press the Start button and you're running. If you want to power on accessories (radio, etc.) without starting the engine, press Start without your foot on the brake.

(3) Stopping - press Start after shifting to P stops the engine and leave accessories powered. Pressing Start a second time powers the car completely off.

(4) Locking - when you leave the car, if you want to lock it (same as the Lock button on the fob), just press your thumb on key area of the door handle for a second and the car locks.

(5) Safety/Security - there is were BMW really thought it through, and seems (to me) to have done good user testing to get this right. CA senses whether or not 'the key' is inside the car, outside in proximity, or not in range and acts accordingly. For example, when I unlocked (put my hand on the door handle and opened it) and invited a friend to get in the drivers seat, they could NOT start the car -- I had the key and was outside! Cool, huh? Also if you leave the car running, it senses that the key is 'gone' and will remain running (for safety; perhaps the key sensor failed) but you can only start the engine within a brief (2 minutes I think) period after it stops (again, for safety in case you stall the engine) before it is imobilized.

So I like it.

Is it worth $1000 extra? Thats a personal call. For me, the answer is yes.

Lovin this car ! -steve-