If you buy new, plan to spend the first 6 months local to the dealership and use everything trying to find issues.
Once you are no longer local, expect dealers to not want to deal with you and if they do, there is normally no time frame for getting the repairs done.
Even at the dealer you bought from, don't expect prompt convenient service. They will take a guy paying full shop rates over discounted warranty work in a heartbeat.
Save the extended warranty money in a maintenance fund...9 times out of 10 you will be far ahead doing so.
PS: Buying new is far from trouble free. Friends buying new have more complaints about repairs than we've had buying used.