Our party came for Happy Hour (Mon-Fri, 4-6pm) and had a fabulous time! We sat in the bar area and had buy one/get one margaritas!
The tri-salsa's that come with the chips are a really nice touch. Even though Isla seems like the poor man's Dos Caminos (at the Palazzo), it is one of the better Mexican restaurants on the Strip.
Only issue with Isla is the tortilla chips...why so hard? Is this because you do not make them onsite?