Well, the Centurion lounges are not as good as the LHR Clubhouse, but they're much closer than anything else you'd find for domestic US travel.

In particular, the food is generally of equivalent quality to a Clubhouse, but with only a buffet, no waiter or menu service. The cocktails (quality of ingredients and novelty of menu offerings) are equivalent to a Clubhouse, except that there is no table waiter service for drinks. There is a spa only in the DFW location (as of now) and it is significantly less elaborate than the VS Clubhouse spas. The overall ambiance is not quite as chic as the Clubhouse, and the Centurion lounges are quite a bit smaller in floor space and therefore don't have the opportunity to offer the multiple different "environments" of the LHR Clubhouse, but the Centurion lounges are still quite nice.