I've ate at a Mr. Lucky's a few times and it's a nice attachment to the Hard Rock.
Most casinos have over priced food, especially nicer, boutique'esq hotels, but the Hard Rock has pretty decent prices for a cafe at the Hard Rock.
I've tried their breakfast and one of their burgers. Both had good flavors, and I didn't spend more than 10 bucks on each of them, I think about the $7-8 range, not bad.