Our favorite japanese curry place closed in Los Angeles like 10 years ago and we've been trying to find something comparable since. Most places are poser curry makers. We can tell that curry zen put their own secret sauce so it doesnt taste generic.
So far we've tried the chicken katsu curry as well as the vegetable curry. Both are very good and tastes like a kick ass home-made meal. The chicken is all white meat which I love! You can also adjust the spiciness according to your risk tolerance. I love spicy foods and I find they tend to make it more spicy than not...so definitely be cautious with selecting spiciness.
Parking can be a headache sometimes but its well worth it. I think they recently renovated the restaurant so its way more spacious than before!