This is certainly not a cheap eatery. it's widely written up and its situation is superb. Sennen Cove is very near Land's End and you can get an appreciation of the natural scenery of the latter without suffering from its commercialism.
We could only speak for the fish dishes among the main courses. Both the Monkfish and the brill were delicious and the atarters and puddings were of matching quality.
I repeat -it's not cheap but if you fancy a one-off treat - - - [actually I think lunches are significantly cheaper]