Update November 25, 2017.
Umami has new ownership and had turned into the typical AYCE sushi place. I've been and was unimpressed with the new service or quality of food. Stay away.
If you're honest with yourself you know there hasn't been any really good sushi in Centennial. When I need sushi I've been willing to drive 20 minutes away for a decent restaurant.
I think Umami may have changed that. My husband and I went recently on a weekday night and sat at the sushi bar. Freshness and flavor were comparable to the better places in Chinatown or on the strip. They had special selections of fish that were not on the menu but offered to us. And this is really important - the sushi chefs were very knowledgeable about different types of fish and flavor. We really like this place and will return!
Things I'd like to see- wi-Fi. If you had Wi-Fi I'd probably eat there every day. I can't come for lunch and be completely detached from work. I'd also like to see options like chirashi or donburi. Not sure if I'm able to order this off the menu--if available, please let me know!