"I've become accustomed to a sunroof, and I'd like to have a Nav system with XM, traffic," why ??? that sets you back 5-6K for almost nothing .. built in NAV is horrendous XM ??? for what ?? traffic you can get that with a decent external NAV and cell phone which you probably already paying for ... so your gps unit a very high end is about 400-500 with all you probably want... traffic streaming everything . your money but not a wise choice ..
I way too regularly spend 2 hours driving home from work, I like XM. I've also used Waze and Google Navigation on my Galaxy S3 and its ability to recognize jams and offer alternatives is underwhelming. Maybe the Toyota system can't do it either, but ideally I'd find something that gives me a heads up of what I am heading into so I can look for alternates. That is what I want Nav for, not necessarily for finding anything.
I haven't read the responses carefully but Entune didn't start until model year 2012. The equipment w/each trim level for 2010-2011 model years were the same but changed a lot for 2012 to current. See Toyota Vehicles : Toyota Announces Prices for 2010 Prius / Toyota for 2010. For '11, they changed nothing other than spelling out the numbers instead of using Roman numerals (MY11 Prius | PriusChat). For '12 and '13, things really changed. See Toyota Prius 2013 | Hybrid Car.
I just went from a 2010 and I love having power seats and auto headlights in the 2012. I also like the front end a lot more.
Not too deviate too much, but how useful is it? My commute home covers approximately ~45 miles, most of which on major highways, where a evening ruining jam can exist at any point. Ideally, I'd find out about it a few miles ahead and be able to hop onto an alternate for a little ways. Of course in this area, that might be jammed too. Right now, unless they mention it on the radio traffic report every 10 minutes, I don't know about it until I hit it.
My commute is very short with this Prius that I hardly use it. If you have a destination active in navigation and check traffic on route button on for me it has been accurate but again I have not given it many tries. I did find that the accident sometimes is cleared and the sig alert is still active on the car.