I have to agree that Diamond Backs does offer one of the best happy hours in town. Their Thursday specials of $4 signature martinis and half-price appetizers (that are pretty much a meal for me) are great deals - not to mention the atmosphere and live music is pretty great. BUT for a regular meal, or even special occasion dinner, I have to say that the food is NOT worth the price you pay.
I have only had the prime rib and some tortilla soup and salad off the regular menu, and they were good - but not as good as they SHOULD be for the price I paid. My meat was bland (of course, I'm all for bold flavors) and cooked incorrectly - I ordered medium-rare and got well-done (no pink left)- and the side of potatoes was what I expect from a chain restaurant.
I hate to give a negative review, and maybe I hit them on a bad evening, but I have heard many people (some of which WORKED at DBs previously) agree that the food is good, but not as upscale as they try to portray.