We have had 3 Priuses (?). A 2005, a 2008 and now a 2010. The 2010 has the solar package that you asked about. I don't know if it really helps to reduce the interior temp or not. I do know that the circulating fan is usually running whenever we get in when it is sitting in the sun. We got this car just prior to moving to FL from VA, so I can't tell if it's better than not havin the solar package in FL, but I have to believe that it has to help. I also try to pop the sun roof to allow the heat to excape, but don't always remember to do it. I don't think the solar package was available prior to 2010. If cargo room is a concern, I suggest that you check out the Prius V. Ours also has a feature to start the A/C before you get in the car, but to be honest, I can't ever remember to do it before we actually get in. You have to be fairly close to do this.
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PriusChat.