Coddu Vecchju

I visited this in march 2003, arriving after dark initially, then returned next day to really see its splendour.
I found it quite a peacefull location, great setting and loads of parking with no fees to pay at that time of year.
I found it to be in very good condition and feel it does give you a sense of what it might look like complete.
With a few Nuraghi towers nearby you could also explore on foot. Combine this with lots of other antiquarian sites in the area a great part of the island to visit.