I won't go into all the details of Roy's. It's a chain and while the menu varies from place to place - it doesn't vary all that much. I personally love the chain It's got great hawaiin and asian-fusion food with "americanized" accents. They make great drinks...even the arnold palmer here tastes better than in other places.
But let me focus on this one in Summerlin for a minute. The two or three times I went, the service was pretty sharp. The location is great only if you happen to live or be staying in Summerlin. It's a bit of trek for tourists from the Strip. It stays fairly quiet inside which is nice and a bit of a change from most other members of the chain. No smoking except in the bar - which is a plus (this is Nevada after all).