I have only stayed at one of the three you asked about, Orbit One. It was very nice, and was our kids favourite place out of all the three different timeshare condos we have rented over the years. It was nicely decorated, very clean and spacious. They really enjoyed the pool area. I would stay there again, but it wouldn't be my first choice but that is because I need to have internet available to keep in contact with clients,and using the internet in the lobby/lounge area was expensive. We would be looking for something that at the very least has either free internet, or internet available in room for a blanket fee (10.00 for 24 hours, or something like that).
Silver Lake is almost always available on skyauction. If we use skyauction next time (we usually do, but are looking at a Windsor Hills condo this time, because of the internet issue) I would take Silver Lake as it is a bigger resort with a convenience store and snack bar/bar on property.
I posted a review of my stay at Orbit One on the review board at the top of this one. You will have to scroll a bit to find it, but it's there.