We stayed in St. Jean de Luz/Ciboure for 2 weeks mid-2016, and enjoyed it.
We did not hire a car (and never do), but used public transport: by bus to Biarritz and Hendaye (buying tickets on the bus), and by train to Bayonne. We also walked for several kilometres along the coastal footpath around Bidart, Guéthary & Socoa - the path was in a good state of repair (local village/town maps from the tourist information offices were helpful in locating access points).
However, car hire might offer greater flexibility and convenience for a short stay.
There was a good choice of restaurants (more so in St. Jean de Luz than Ciboure), and those that we enjoyed were: L'Ephémère (Quai Maurice Ravel, Ciboure), Zoko Moko (Rue Mazarin, St. Jean, twice), La Réserve (hotel, Rue Gaëtan de Bernoville, on the northern outskirts of St. Jean de Luz), La Vieille Auberge (Rue Tourasse, St. Jean, exceptional value), and, Le Xaya Restaurant (Rue Saint-Jean, St. Jean). The regional red wine that we tasted was very agreeable, e.g., Domaine Mourguy (Appellation Irouléguy), as was the Rioja.