I would recommend, after SR 41 and SR 46 merge (near the Parfield turn-off), that you stay of SR 46 to Paso Robles & then take US 101 south. SR 41 from Shandon to the coast is a bit crooked although a nice drive if you don't mind the curves. SR 46 is a much better road.
BTW, Parkfield is the location of the US geological survey center where the movement of the famous San Andreas fault is measured and studied. Neat little town to visit.
I would also recommend taking SR 46 over to the coast from US 101. A very nice drive through the central coast wine country and, when you merge onto RT 1, you can go north to Cambria or south through Cayucos to Morrow Bay.
If you go to Cayucos, Duckie's (by the pier) has great chowder.