I've had my U300 for just over 4 years now. When the U150 came out I initially thought is was 90+% of the U300. But I never did a side by side comparison. Then 2 years ago at Axpona on the last day that they were showcasing the U150 and someone bought it on the spot and took it away around noon. They had an U300 there just for show but used it when the U150 left. That's when I changed my mind and can say the U150 is closer to 80% of the U300. The U300 has a much richer more detailed sound.
That said Aavik showed their new U380 at RMAF. I wasn't there so I can't comment on it. Supposed to be much better than the U300
That said Aavik showed their new U380 at RMAF. I wasn't there so I can't comment on it. Supposed to be much better than the U300