There is no simple answer to your questions. Consider these things:-
you are buying a 10 year old vehicle which WILL need parts replaced.
you will need to find a good mechanic to do repairs on a supercharged motor.
you will consume much more fuel with the HD.
depending on your location, your auto insurance may increase with this specialized vehicle.
there is a price to pay for speed and looks!

Good luck with your potential purchase. I have owned my HD since May 2002 and have put on all 102,000 miles. It has been a great truck but is starting to cost more money as I replace some parts.