For years we've promised to take our son to Vegas for his 21st birthday this coming July. The group has grown to about 30, and we plan to take them all out to dinner on a Saturday night. If the choice were mine we'd do something nice like Rosemary's. But my son, a wonderful child in other matters, does not like "fru-fru" places. (One night when I took him and his girlfriend out in Sonoma, his choice was one of the brew-pubs, rather than any of the more upscale places most chowhounds would prefer.) So we need something in Vegas that would be fun, could handle a group of 30, isn't super expensive, and has a rather basic menu. Help!