A friend did one of these once for a trip to Vegas. It was mid-week, and until a couple days before, all they got were flight dates, no times, but they put them up on LVB. Once they finally got out of the presentation after saying no 100 times (the sales staff are PERSISTENT), it was smooth sailing getting everything organized. So it CAN be done. A cruise is more expensive than a few days in Vegas though, so there might be even more pressure to buy whatever they're selling.