Originally Posted by JCL

Since you are under warranty, I wouldn't let anyone but the BMW dealer do it. Don't give them a reason to put your warranty coverage in doubt. If you introduce a third party, you create additional risk. You won't be concealing the fact that the fluid was changed by using a third party, it won't be a secret later, so it comes down to who you can hold responsible if there is a problem. Better to have OTTC (One Throat to Choke).