The owners of the farm have turned the site into a commercial attraction by the way that the tractor rides are organised, and it forms part of the greater 'day out' experience of Henblas.
That said, I think it is well worth the visit just because of it's location.
It is very easy to understand why the monument was built there. The views towards Snowdonia on the mainland are spectacular, and without any scientific evidence (no compass with me etc) there is an awsome view towards two peaks in the mountains which one could imagine may form some sort of alignment in the V of the pass.