Giada's Italian Cucina has excellent food and good service. We went on a Saturday night. The restaurant has about 20 tables, so reservations are a great idea if you plan on going to Giada's on a potentially busy night.
We ordered a calamari appetizer and it was one of the best we've had in Las Vegas in quite some time. The chicken convertino was an interesting dish I haven't had before, and it was really good. My wife's eggplant parmigiana was also excellent. Each entree came with a yummy salad too. The food all came to the table quickly and was the perfect temperature. Portions were just the right size (not gargantually large, not too small to leave you hungry).
We used a Groupon coupon and they gladly accepted it. The only problem was that when the restaurant filled up, the only waitress was way overworked and service declined (really not her fault). It would help the restaurant if they increased the wait staff during potentially busy nights, but if the place is empty then they would be overstaffed. A tough call for a small place like this.
For really great Italian food in the Henderson area, Giada's is an excellent choice.