We continue to hear stories about car buyers who discover that their new vehicle isn't compatible with their existing handset, or vice versa. Just last fall, TheCarConnection.com tried to step in—to no avail—and help the buyer of an Audi A4 who had discovered their Blackberry Tour wasn't compatible. Turns out it simply wasn't going to be fully compatible, but in most cases that's not justification to return the car or ask for money back.
There are certainly plenty of aftermarket solutions for vehicles, along with a number of dealer-installed systems, but don't expect them to satisfy if you're a frequent user, or to be an all-out substitute for an original-equipment system. We've found the bulk of these add-ons to be disappointing due sometimes to their difficult interfaces but more often for their lack of ability to filter out road noise. OEM systems seem to be much better integrated, and you'll find yourself speaking more naturally, not shouting.
The underlying message here is, don't take anyone's word that your phone is going to pair properly. Bring the phone that you're going to use—at least in your first year or two with the car—out on the test drive and have the salesperson show you how to properly pair it. If he or she can't get it to work, don't count on it.