I don't prefer either. Both places make some outstanding wines and both places make some plonk. The same is true of many other places.
I drink wines that come from all over the world: California, France, Italy, Germany, Austria, Spain, Portugal, Australia, New Zealand, Chile, Argentina, and occasionally a few others. I choose the wine based on things like its price and the quality I expect from (either because of its reputation or because I know the wine) the *particular* wine, not where it comes from.
I strongly recommend that you do the same. Choose your wines individually, not by country.