Penfold's are widely available in the US (even in Kansas!) and they are great red wines. Excellent examples at multiple price points. Yellowtail is no comparison.
There are too many fine California Cabernet Sauvignons to list. I personally like Silverado's Solo. Pick up a couple at a time and find what you like. I have discovered a lot in the 12 to 20 dollar range that are very nice. It's like other things, there are some in the lower price ranges you will enjoy, but you're more likely to find winners as the price goes up.
My wife and I loved Temecula when we visited the area a few years ago, if we could afford to move there I think we would.
