polar package. changes over time?

[AvairY-BC]

Hi,
I'm looking at getting into an RV -probably a 29-30 foot cougar with bunkhouse and polar package- year round in southern BC. It is often -10 to 15 degrees for the winter(14-5 degrees F) I know the 'polar package' is different than a winter package, and wondering if anyone knows how the cougar's polar package has changed between the 2007 models and 2014. Has the quality of the polar package changed and if so how? or where can I find this out?

THank you
Avairy =}