I purchased my Nitro 4.0L R/T last year. I now have 16.9K miles. I still love it. Had a little noise in the engine compartment it was a loose power steering belt. Also, had a rattle coming from the leading edge of the roof rail. The leading edge of the roof rail is held down with double sided tape. Still a cool vehicle and its still nice and easy to me.
Since it's winter time I love the electric start and the heated seats.
I'll get back with you about the improvements needed.