I have never gone on a formal
DVC tour, since we bought sight unseen.
However, I do know that DVC is
not like other high pressure timeshares who browbeat you, take your keys and won't let you leave, etc. DVC pretty much sells itself, and most of the sales personnel (Guides) are pretty low key and willing to spend as much time as you'd like with them.
One tip....read these boards, learn about DVC here, and ask lots of questions before you go to WDW. I advise this for two reasons:
1. You'll have a much less overwhelming experience if you already know 90% about how DVC works, etc. Without that knowledge, you will get a ton of information that will be difficult to digest. If you already know most of the information, you can concentrate your tour time on getting an impression of the accommodations and asking a few key questions instead of a deluge.
2. Disney often has incentives which you only have 72 hours to exercise after taking the tour. They are very firm with the 72 hour timetable so you want to have a pretty good idea if DVC is for you or not before you go. The sales experience will be much better for it.
Like many people here, I learned about DVC rules and such via these boards. By the time I called my Guide, I pretty much had a handle on things and was ready to purchase over the phone. I don't think I would have ever done that without the pre-work I did here.
Good luck and enjoy your trip!
