Since joining this forum I've noticed that this questions seems to come up more and more. I thought it may be handy to put together a flowchart of what your options are if you want to upgrade to either the new facelift lights or the pre-facelift LED kit. Shout out to DaveB8 for helping me understand most of this.
This is correct as of 25/03/2012.
Notes:
I believe that in addition to Kufactec, Europrice offer a similar kit which may make more sense for North American owners (rather than importing from Kufatec in Europe).
The central convenience module MUST be coded by Audi or authorised agent (with access to SVM update kit) if it is replaced. This module is also responsible for start key authorisation and therefore your car WILL NOT START unless the new module is coded.
Kufatec Links:
Pre-Facelift: http://www.kufatec.de/shop/product_info.php/info/p1406_c274_Bundle-LED-Rear-Lights-Audi-A5--S5.html
Post-Facelift: http://www.kufatec.de/shop/product_...oduct_info.php/info/p9174_c274_Bundle-LED-Rear-Lights-Audi-A5--S5-Facelift.html
Note Kufatec also sell the kit minus the actual lights if you want to source the light units on your own.
DaveB8 contact:
http://www.audienthusiasts.com/Contact.html
This is correct as of 25/03/2012.

Notes:
I believe that in addition to Kufactec, Europrice offer a similar kit which may make more sense for North American owners (rather than importing from Kufatec in Europe).
The central convenience module MUST be coded by Audi or authorised agent (with access to SVM update kit) if it is replaced. This module is also responsible for start key authorisation and therefore your car WILL NOT START unless the new module is coded.
Kufatec Links:
Pre-Facelift: http://www.kufatec.de/shop/product_info.php/info/p1406_c274_Bundle-LED-Rear-Lights-Audi-A5--S5.html
Post-Facelift: http://www.kufatec.de/shop/product_...oduct_info.php/info/p9174_c274_Bundle-LED-Rear-Lights-Audi-A5--S5-Facelift.html
Note Kufatec also sell the kit minus the actual lights if you want to source the light units on your own.
DaveB8 contact:
http://www.audienthusiasts.com/Contact.html