Not sure what to say about Allegro. The restaurant is nice, and the food is ok, but the outrageous cost of the food ($30 for a person pizza) really makes me question its worth.
The positive is that it's open late (but most places in Vegas are) ... and the food is good ... but if you're going for cheap eats then this isn't the place for you.
Overall I don't think the quality of the food justifies the cost. But that's just me.
Stay Cheerful ;)