I had this discussion with someone recently and I thought I'd bring it here as well. The impression I got while watching TNG, DS9 and VOY was that Quark's civilian holosuites were more sophisticated than the ones on the Enterprise D and Voyager. Maybe it's because civilian technology can often better than what you find on US naval ships. Maybe it's because Quark's holosuites allowed for more freedom than the Starfleet holodecks... or just that Quark's holosuites seemed smaller than those on the Enterprise, yet seemed able to simulate just as many environments.