I rode this route today ... to put it simply. It’s AWESOME!! Loved it!
Its very bumpy so might not suit your average sports bike rider but its exactly the type of road I love [I ride a ZX6-R].
This road is essentially an open moor road with well sighted corners and plenty of knee-down opportunities.
It’s the type of road you can really ride FLAT out and use all the revs your bike has available.
Awesome road over the mountain - watch out for the Welsh ARmy training if the red flag is out