Note, I have not eaten here for lunch or other off-peak times. I have only been to Lahaina during traditional dinner times (7pm-9pm) and happy hour/early dinner times (5pm-7pm) and the sushi has always been excellent.
My favorite order is just regular salmon (sake) sashimi. A huge plate of it. Their Ultimate Salmon rolls and Ultimate Hamachi rolls are very good too. The salmon, everytime I've been here, is beautifully colored with healthy lines of fat and has that wonderful taste and texture that you expect from excellent raw salmon.
Service has always been very good for me as well.
The decor is a little strange with the "star-lit" ceiling and such, but it's a solid sushi option when in the Summerlin area.