I believe what the other posters are trying to share is that you must be very careful with your credit. The more you preserve those scores by not taking 'risky' loans (i.e. high percentage rates) the more you can do in the future.
And for the record, I have purchased two new cars. One had a three year loan that we paid off in a year and the second we paid for with a bonus. Ten years later we still have those cars and will take care of them until we can afford to purchase without taking out long term loans.
DVC purchase paid on Amex (to get the points for airfare) and paid off the next month.
Both of our houses with loans well under 4%. We could purchase the second house BECAUSE we have been careful and waited.
So no, any interest
paid is not worth the money. The stress involved by knowing the money is essentially being thrown away is too great. And this is from a person who paid for her DVC points direct. I don't regret that decision because of how we use our points at times. But at no time will I threaten my credit scores because of my decisions.