First time Prius owner, Ottonavi or Alpine Perfect Fit

coming from a 2004 Matrix, never had Nav or touch screen. Jut got the 2012 Prius-ii pkg (i believe thats what it is) , No-JBL option.

I am very much interested in upgrading to a NAV + speakers (but nothing super fancy like amps, or subwoofer etc.) After reading thru the forums looks like Ottonavi has good OEM for 2012 model.
and I am very much impressed by the INA-Z928HD install pic from BlackSpade.

Three things will be used most: GPS (US/Canada), MP3 and IPhone 5 compatibility
XM, Pandora, DVD player etc. are not the features I am into, but if Alpine is way better in long run I would rather pay once and get over with it.

Please advise on comparision of Ottonavi vs. Alpine on the above needs. Does it fit "u get what you pay for" ? Is Alpine worth twice the price? will it give better output to decent aftermarket speakers. Just checking here before I make my move and have buyers remorse later.
thanks for all the good info here. Cheers!