For those who have questions about BMW's extended warranty plans, they have different coverage levels based off if your car is, or is out of the original warranty period (4 yrs/50K miles).
**I have BMW's extended warranty Platinum level, which is their top tier coverage. So far it's paid for replacing the SMG clutch position sensor, front bushings, and some other items.
**I paid $4991 for an additional two years / up to 100K miles.
**The advantage is that it's a BMW backed warranty, works at every BMW dealer, and there shouldn't be any arbitration (none that I've experience at least). The disadvantage is that it is only honored at BMW dealerships and does not allow you the flexibility to take your car to an Indy shop. 3rd Party warranties are more flexible and if your Indy shop accepts the insurer, you can take it to places of your choosing, including BMW dealerships. However, depending on the warranty company, they may have to have a claims adjuster come visit and the process can be a bit long (so I've heard and seen people gripe about on this board). More often than not, it's just a quick phone call from your Service Dept to the insurer.
This chart below depicts coverage for in/out of warranty (I think M cars are either category D or E - I forget which):
For buying a warranty for cars still in original warranty period, there are three coverage levels:
Each level provides varying coverage, the platinum being the most comprehensive. However, none are all inclusive as the original 4 yr/50k warranty.
Powertrain is minimal, covering major mechanical components, and is pretty much the equivalent to BMW's CPO program (so I've been told).
That said, Platinum is an exclusionary warranty and items that are not covered are listed in the contract. Warranty booklet and sample contracts are attached in PDF form.
Pics of Contract listing items excluded:
Prices vary from dealer to dealer. Each dealer tries to mark up the warranty costs. The best thing to do is shop around and pit dealers against each other to drive costs down.
Also, here are threads discussing BMW's warranty with input from members such as Bruce M, myself, and others