PZEV, Also called as California spec., is a higher standard for emission but has nothing to do with engine performance. It has 3 catalytic converters rather than normally one, 5 oxegen sensers rather than 2. So after 5 years of driving, warranty expired, you may have much higher chance to get emmision error codes and difficult to diagnose and costly to repair. Subaru makes great cars for snow country, just buy the regular one. You may buy "limited" to get better sound and leather etc. In Carlifornia and some New England states, unfortunately, it is mendatory.