Yesterday and today I visited some sites of the "domus de Janas" sites.

1) Anghelu Ruju near Alghero. This site is rather big with some 40 graves. There is entrance fee, and good explanation. 

2) Su Crucifissu Mannu near Porto Torres. This site is near a farm. You can free visit. No entrance fee, no explanation. Not so many graves.

3) Altar of Monte d' Accoddi between Porto Torres and Sassari. This one is not similar at all to the other ones, but in my opinion most interesting site from the ones I saw. It is build in third millennium before Christ. 

4) Sennori: near the buildings of the commune; you need to get the key there and return to the same place.  

5) Su Murrone in Chiaramonte: in the middle of the fields, no entrance fee, no explanation. Not so many graves.

6) Elefant Domus de Janus in Castel Sordo: one or two domus de janas. Most interesting about this one is the shape of the rock. I think 99 % from the visitors comes for the shape and not for the grave.

7) Necropolis of Montalè in Sassari: not worth the detour. Behind a fence and very small (i think just one).

Conclusion: i am charmed by some of the parts of this "domus de janas"; for me definitely a yes; I would only keep 1) and 3) from this ones.