Thanks for the comments. To be honest, the traffic is my main concern about the I Drive Grand Vacations. It seems the overpass is now open, but that area does appear to be very busy.
I think I prefer to pay a bit extra for the Grand Vacations places, especially as they seem to come with balconies, which I tend to use a lot in the evenings. I think I'll wait until Parc Soleil opens up for bookings and then decide whether it's worth paying the extra. Reviews seem better there, the location a bit better and parking a lot better.
Thanks again for your help.